Plasma anisotropy around a dust particle placed in an external electric field.

A self-consistent model of plasma polarization around an isolated micron-sized dust particle under the action of an external electric field is presented. It is shown that the quasineutral condition is fulfilled and the formed volume charge totally screens the dust particle. The ion focusing and wake formation behind the dust particle are demonstrated for different ion mean free paths and the external electric fields. It is obtained that at low values of the external electric field the trapped ions play the main role in the screening of the dust particle charge. For high external electric fields, the density of trapped ions decreases and the dust particle is screened mainly by the free ions.

Canadian consensus guidelines on long-term nonsteroidal anti-inflammatory drug therapy and the need for gastroprotection: benefits versus risks.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used, but are not without risks. AIM: To provide evidence-based management recommendations to help clinicians determine optimal long-term NSAID therapy and the need for gastroprotective strategies based on an assessment of both gastrointestinal (GI) and cardiovascular (CV) risks. METHODS: A multidisciplinary group of 21 voting participants revised and voted on the statements and the strength of evidence (assessed according to GRADE) at a consensus meeting. RESULTS: An algorithmic approach was developed to help manage patients who require long-term NSAID therapy. The use of low-dose acetylsalicylic acid in patients with high CV risk was assumed. For patients at low GI and CV risk, a traditional NSAID alone may be acceptable. For patients with low GI risk and high CV risk, full-dose naproxen may have a lower potential for CV risk than other NSAIDs. In patients with high GI and low CV risk, a COX-2 inhibitor plus a proton pump inhibitor (PPI) may offer the best GI safety profile. When both GI and CV risks are high and NSAID therapy is absolutely necessary, risk should be prioritized. If the primary concern is GI risk, a COX-2 inhibitor plus a PPI is recommended; if CV risk, naproxen 500 mg b.d. plus a PPI would be preferred. NSAIDs should be used at the lowest effective dose for the shortest possible duration. CONCLUSION: More large, long-term trials that examine clinical outcomes of complicated and symptomatic upper and lower GI ulcers are needed.

Acute toxicity and 2-year adverse effects of 30 Gy in five fractions over 15 days to whole breast after local excision of early breast cancer.

AIMS: A pilot study was undertaken with the aim of documenting acute skin reactions and 2-year late adverse effects of a five-fraction course of adjuvant whole breast radiotherapy delivered over 15 days after local tumour excision of early breast cancer. MATERIALS AND METHODS: Thirty women with early invasive breast cancer aged>or=50 years with a pathological tumour size<3 cm, complete microscopic resection, negative axillary node status and no requirement for cytotoxic therapy were prescribed 30 Gy in five fractions over 15 days to the whole breast using tangential 6-10 MV X-ray beams and three-dimensional dose compensation with written informed consent. Post-surgical baseline photographs of the breasts were taken, and acute skin erythema and moist desquamation were each scored weekly for 7 weeks using four-point graded scales (grade 0=none, 1=mild, 2=moderate, 3=severe). This was followed by an annual clinical assessment, including repeat photographs at 2 years. RESULTS: Nine patients (30%, 95% confidence interval 14.7-49.4%) developed grade 2 erythema, with the remaining 21 patients developing milder degrees of reaction. Four (13.3%, 95% confidence interval 3.7-30.7) patients developed moist desquamation, grade 1 in three women and grade 2 in the fourth. At 2 years after treatment, 23/30 (77%) patients scored no change in photographic breast appearance compared with the pre-treatment baseline; seven (23%, 95% confidence interval 9.9-42.3) scored a mild change in breast appearance, and none developed a marked change. After a mean follow-up of 3.1 years (standard deviation 0.37, range 2.1-3.9 years) there have been no ipsilateral local tumour relapses. CONCLUSIONS: Further evaluation of a five-fraction regimen of adjuvant whole breast radiotherapy in a phase III randomised trial is justified, including a regimen delivered in a total of 5 days.

Systematic reviews of the clinical effectiveness and cost-effectiveness of proton pump inhibitors in acute upper gastrointestinal bleeding.

OBJECTIVES: To evaluate the clinical effectiveness and cost-effectiveness of proton pump inhibitors (PPIs) in the prevention and treatment of acute upper gastrointestinal (UGI) haemorrhage, as well as to compare this with H2-receptor antagonist (H2RA), Helicobacter pylori eradication (in infected patients) or no therapy, for the prevention of first and/or subsequent bleeds among patients who continue to use non-steroidal anti-inflammatory drugs (NSAIDs). Also to evaluate the clinical effectiveness of PPI therapy, compared with other treatments, for the prevention of subsequent bleeds in patients who had previously experienced peptic ulcer (PU) bleeding. DATA SOURCES: Electronic databases and major conference proceedings were searched up to February 2006. REVIEW METHODS: Data were collected from the systematic reviews addressing each research objective. These were then entered into an economic model to compare the costs and quality-adjusted life-days of alternative management strategies over a 28-day period for patients who have had UGI bleeding. A Markov model with a Monte Carlo simulation used data from the systematic reviews to identify the most cost-effective treatment strategy for the prevention of UGI bleeding (first and subsequent) among NSAID users using an outcome of costs per quality-adjusted life-years (QALYs) over a lifetime from age 50 years. RESULTS: PPI treatment initiated after endoscopic diagnosis of PU bleeding significantly reduced re-bleeding and surgery compared with placebo or H2RA. Although there was no evidence of an overall effect of PPI treatment on all-cause mortality, PPIs significantly reduced mortality in subgroups when studies conducted in Asia were examined in isolation or when the analysis was confined to patients with high-risk endoscopic findings. PPI treatment initiated prior to endoscopy in UGI bleeding significantly reduced the proportion of patients with stigmata of recent haemorrhage (SRH) at index endoscopy compared with placebo or H2RA, but there was no evidence that PPI treatment affected clinically important outcomes. Giving oral PPI both before and after endoscopy, with endoscopic haemostatic therapy (EHT) for those with major SRH, is preferred to all others on cost-effectiveness grounds at any threshold over 25,000 pounds per QALY, even if only short-term effects are taken into account, and at any threshold over 200 pounds per life-year gained if long-term effects are included. The risk of NSAID-induced endoscopic gastric and duodenal ulcers was reduced by standard doses of PPI and misoprostol, and double doses of H2RAs. Standard doses of H2RAs reduced the risk of endoscopic duodenal ulcers. PPIs reduced NSAID-induced dyspepsia. PPIs were superior to misoprostol in preventing recurrence of NSAID-induced endoscopic duodenal ulcers, but PPIs were comparable to misoprostol in preventing the recurrence of NSAID-induced endoscopic gastric ulcers. Full-dose misoprostol reduced bleeding, perforation or gastric outlet obstruction due to NSAID-induced ulcers, but misoprostol was poorly tolerated and associated with frequent adverse effects. H. pylori eradication treatment was equally effective with PPI treatment for the primary or secondary prevention of endoscopic ulcers in NSAID users. H. pylori eradication treatment was more effective than placebo for the primary prevention of endoscopic PU and for the prevention of re-bleeding from PU in NSAID users. With regard to primary and secondary prevention of bleeding PU in NSAID users, the two most cost-effective strategies are H. pylori eradication alone, and H. pylori eradication followed by misoprostol (substituted by a PPI, if misoprostol is not tolerated) at an additional 4810 pounds per QALY. In patients who had previously experienced a bleed from a PU, re-bleeding was less frequent after H. pylori eradication therapy than after non-eradication antisecretory therapy, whether or not the latter was combined with long-term maintenance antisecretory therapy. CONCLUSIONS: PPI treatment compared with placebo or H2RA reduces mortality following PU bleeding among patients with high-risk endoscopic findings, and reduces re-bleeding rates and surgical intervention. PPI treatment initiated prior to endoscopy in UGI bleeding significantly reduces the proportion of patients with SRH at index endoscopy but does not reduce mortality, re-bleeding or the need for surgery. The strategy of giving oral PPI before and after endoscopy, with EHT for those with major SRH, is likely to be the most cost-effective. Treatment of H. pylori infection was found to be more effective than antisecretory therapy in preventing recurrent bleeding from PU. H. pylori eradication alone or eradication followed by misoprostol (with switch to PPI, if misoprostol is not tolerated) are the two most cost-effective strategies for preventing bleeding ulcers among H. pylori-infected NSAID users, although the data cannot exclude PPIs also being cost-effective. Further large randomised controlled trials are needed to address areas such as PPI administration prior to endoscopic diagnosis, different doses and administration of PPIs, as well as the primary and secondary prevention of UGI bleeding.

A comparison of the cost-effectiveness of five strategies for the prevention of non-steroidal anti-inflammatory drug-induced gastrointestinal toxicity: a systematic review with economic modelling.

OBJECTIVES: To assess the relative effectiveness, patient acceptability, costs and cost-effectiveness of four strategies for the prevention of non-steroidal anti-inflammatory drugs (NSAIDs)-induced gastrointestinal (GI) toxicity: (1) Cox-1 NSAIDs plus histamine-2 receptor antagonist (H2RA), (2) Cox-1 NSAIDs plus proton pump inhibitors (PPIs), (3) Cox-1 NSAIDs plus misoprostol, and (4) Cox-2 NSAIDs (later expanded to 4a Cox-2 coxibNSAIDs and 4b Cox-2 preferential NSAIDs). DATA SOURCES: Electronic databases up to May 2002. REVIEW METHODS: Relevant studies were selected, assessed and analysed. Pooled relative risk ratios (RR) from the systematic review were combined with up-to-date UK resource use and unit costs data in an incremental economic analysis. A probabilistic decision-analytic model was designed and populated with data to carry out incremental economic analysis. Incremental cost-effectiveness ratios (ICERs) were generated for the outcome measure, endoscopic ulcer or serious GI event averted, against total cost, and non-parametric bootstrapping was used to simulate variance of these ICERs. RESULTS: Of 118 selected trials, including 125 relevant comparisons (which included 76,322 participants) only 138 deaths and 248 serious GI events were reported. Seven comparisons were judged to be at low risk of bias. Comparing the gastroprotective strategies against placebo, there was no evidence of effectiveness of H2RAs against any primary outcomes (few events reported), PPIs may reduce the risk of symptomatic ulcers [RR 0.09, 95% confidence interval (CI) 0.02 to 0.47], misoprostol reduces the risk of serious GI complications (RR 0.57, 95% CI 0.36 to 0.91) and symptomatic ulcers (RR 0.36, 95% CI 0.20 to 0.67), Cox-2 'preferentials' reduce the risk of symptomatic ulcers (RR 0.41, 95% CI 0.26 to 0.65) and Cox-2 'coxibs' reduce the risk of symptomatic ulcers (RR 0.49, 95% CI 0.38 to 0.62) and possibly serious GI events (RR 0.55, 95% CI 0.38 to 0.80). All strategies except Cox-2 'preferentials' reduce the risk of endoscopic ulcers. There were only 12 direct comparisons between gastroprotective strategies. All they suggest is that Cox-2 preferentials are better than misoprostol for preventing GI complications. Indirect comparisons suggested that PPIs may prevent symptomatic ulcers better than Cox-2 coxibs, but this is very weak evidence. For prevention of endoscopic ulcers PPIs and misoprostol appear more successful than H2RAs and misoprostol is better than Cox-2 preferentials. There were no UK head-to-head published economic analyses with regard to the main gastroprotective strategies. There were generally insufficient data with regards to cardiac or renal outcomes, serious GI outcomes or life-years gained to populate the mode. Mean (2.5th and 97.5th percentile) costs per endoscopic ulcer averted compared with Cox-1 NSAIDs alone were as follows: Cox-1 plus H2RAs, -186 pounds (-555 to 804); Cox-1 plus PPIs, 454 pounds (251 to 877); Cox-1 plus misoprostol, 54 pounds (-112 to 238); Cox-2 selective NSAIDs, 263 pounds (-570 to 1280), or Cox-2 specific NSAIDs, 301 pounds (189 to 418). With regard to the prevention of endoscopic ulcers, Cox-1 NSAID plus H2RA is a dominant option. Cost-effectiveness acceptability analysis showed a 95% probability that this combination was less costly and more effective. Cost-effectiveness acceptability frontiers showed that if the decision-maker is willing to pay up to 750 pounds to avoid an endoscopic ulcer, then Cox-1 plus H2RA is the optimal strategy. If the decision-maker is willing to pay over 750 pounds, the optimal strategy is NSAID plus misoprostol. Between 1900 pounds and 3750 pounds, Cox-2 selective inhibitors are optimal, and over 3750 pounds, Cox-2 specific inhibitors become optimal. NSAID plus PPI is never the optimal strategy. Sensitivity and subgroup analyses suggest that Cox-1 NSAID plus H2RA and Cox-1 NSAID plus misoprostol become more cost-effective in the older age group. Some conclusions were associated with high levels of uncertainty. CONCLUSIONS: Although there is a very large body of evidence comparing Cox-2 NSAIDs with Cox-1 NSAIDs, this is not matched by studies of the other types of gastroprotectors or by studies directly comparing active gastroprotective strategies. This lack of direct comparisons led to the use of indirect comparisons to help understand the relative efficacy of these strategies. Indirect evidence in itself is weak and was also hampered by lack of evidence in the underlying studies (where the gastroprotectors were compared with placebo). Economic modelling suggests that Cox-1 NSAID plus H2RA or Cox-1 NSAID plus PPI are the most cost-effective strategies for avoiding endoscopic ulcers in patients requiring long-term NSAID therapy. All strategies other than Cox-2 selective inhibitors reduce the rate of endoscopic ulcer compared with Cox-1 alone. The economic analysis suggests that there may be a case for prescribing H2RAs in all patients requiring NSAIDs. Misoprostol is more effective, but is associated with a greater cost and GI side-effects which may be unacceptable for patients. However, when assessing serious GI events, the economic analysis is sufficiently weakened by the data available as to render clear practice recommendations impossible. Further large, independent RCTs directly comparing various gastroprotective strategies are needed. These should report items such as major outcomes, primary data, adverse events, assessment of practice and patient preference.

Incidence, pattern and timing of brain metastases among patients with advanced breast cancer treated with trastuzumab.

We aim to investigate the incidence, patterns and timing of brain metastases in advanced breast cancer patients who have previously received trastuzumab. Eighty-seven patients who had received trastuzumab for advanced breast cancer from November 1999 to September 2003 at the Royal Marsden Hospital were assessed. With a median follow-up period of 11 months from commencing trastuzumab, 23 patients developed brain metastases (30% at 1 year; 95% CI 58-82%). Among 57 patients who had clinical benefits on trastuzumab, 12 (21%) patients developed first disease progression in brain with 75% of them had isolated CNS progression. Moreover, among patients who received trastuzumab as first line treatment, isolated brain metastases were the initial site of progression in 17% patients. Nearly all patients developed parenchymal brain disease. This study shows brain metastases are common phenomenon in HER2 positive advanced breast cancer patients receiving trastuzumab and also may implicate the brain as a sanctuary site for early relapse in this patient cohort.

Prevention of NSAID-induced gastroduodenal ulcers.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) are important agents in the management of arthritic and inflammatory conditions, and are among the most frequently prescribed medications in North America and Europe. However, there is overwhelming evidence linking these agents to a variety of gastrointestinal (GI) toxicities. OBJECTIVES: To review the effectiveness of common interventions for the prevention of NSAID induced upper GI toxicity. SEARCH STRATEGY: A literature search was conducted, according to the Cochrane methodology for identification of randomized controlled trials in electronic databases, including MEDLINE from 1966 to June 2002, Current Contents for 6 months prior to June 2002, EMBASE to February 2002, and a search of the Cochrane Controlled Trials Register from 1973 to 2002. Biosis Previews(R), ADIS LMS Drug Alerts, Pharmaceutical News Index (PNI)(R) were searched to June 2002. New articles since the last search update were evaluated. Recent conference proceedings were reviewed and content experts and companies were contacted. SELECTION CRITERIA: Randomized controlled clinical trials (RCTs) of prostaglandin analogues (PA), H2-receptor antagonists (H2RA) or proton pump inhibitors (PPI) for the prevention of chronic NSAID induced upper GI toxicity were included. DATA COLLECTION AND ANALYSIS: Two independent reviewers extracted data regarding population characteristics, study design, methodological quality and number of patients with endoscopic ulcers, ulcer complications, symptoms, overall drop-outs, drop outs due to symptoms. Dichotomous data was pooled using RevMan V4.1. Heterogeneity was evaluated using a chi square test. MAIN RESULTS: Forty RCTs met the inclusion criteria. All doses of misoprostol significantly reduced the risk of endoscopic ulcers. Misoprostol 800 ug/day was superior to 400 ug/day for the prevention of endoscopic gastric ulcers (RR=0.17, and RR=0.39 respectively, p=0.0055). A dose response relationship was not seen with duodenal ulcers. Misoprostol caused diarrhea at all doses, although significantly more at 800 ug/day than 400 ug/day (p=0.0012). Misoprostol was the only prophylactic agent documented to reduce ulcer complications. Standard doses of H2RAs were effective at reducing the risk of endoscopic duodenal (RR=0.36; 95% CI: 0.18-0.74) but not gastric ulcers(RR=0.73; 95% CI:0.50-1.09). Both double dose H2RAs and PPIs were effective at reducing the risk of endoscopic duodenal and gastric ulcers (RR=0.44; 95% CI:0.26-0.74 and RR=0.40;95% CI;0.32-0.51 respectively for gastric ulcer), and were better tolerated than misoprostol. REVIEWER'S CONCLUSIONS: Misoprostol, PPIs, and double dose H2RAs are effective at preventing chronic NSAID related endoscopic gastric and duodenal ulcers. Lower doses of misoprostol are less effective and are still associated with diarrhea. Only Misoprostol 800ug/day has been directly shown to reduce the risk of ulcer complications such as perforation hemorrhage or obstruction.

Decision aids for people facing health treatment or screening decisions.

BACKGROUND: Decision aids are interventions designed to help people make specific and deliberative choices among options (including status quo) by providing (at a minimum) information on the options and outcomes relevant to a person's health status. A systematic review is needed to summarize what is known about their efficacy. OBJECTIVES: 1. To create an inventory of existing decision aids. 2. To conduct a systematic review of randomized controlled trials of decision aids aimed at improving people's decision making and outcomes. SEARCH STRATEGY: The following electronic databases were searched: MEDLINE, EMBASE, PsycINFO, CINAHL, Aidsline, Cancerlit, the Cochrane Controlled Trials Register. In addition, individuals known to be active in the field of decision support were contacted. SELECTION CRITERIA: We screened titles and abstracts for all interventions providing structured, detailed, and specific information on treatment or screening options and outcomes to aid decision making. Information about the decision aids was compiled in an inventory and those evaluated in a randomized controlled trial were reviewed in detail. DATA COLLECTION AND ANALYSIS: Using Cochrane review methods, two reviewers independently screened and extracted data on several evaluation criteria. Results of randomized trials were pooled using weighted mean differences and relative risks with all data analysed using a random effects model. MAIN RESULTS: Eighty-seven decision aids were identified. Twenty-three of them had been evaluated in 24 randomized controlled trials. Among the trials comparing decision aids to usual care interventions, decision aids performed better in terms of: a) greater knowledge of options in seven of seven studies (weighted mean difference (WMD = 19 out of 100, 95% confidence interval (CI): 13,25); b) more realistic expectations in two of three studies (RR=1.48 95%CI 1.02, 2.14); c) lower decisional conflict related to feeling informed in three of three studies (WMD = -9.0 of 100 95%CI: -15, -3); d) reducing the proportion of people who were passive in decision making in three of four studies (RR = 0.63, 95% CI: 0.5, 0.8). When simpler decision aids were compared to more detailed ones, the relative improvement was significant in: a) improved knowledge in two of seven studies (WMD = 4 out of 100, 95% CI: 2, 5); b) realistic expectations in two of two studies (relative risk (RR ranged from 1.5 95%CI: 1.3,1.8); and c) decisional conflict in one of two studies (WMD= -4 95% CI -8,-0.2). There was a consistent trend for decision aids to do no better than comparison interventions in affecting: satisfaction with the decision in five of six studies, satisfaction with the decision making process in four of five studies, and anxiety in four of five studies. Decision aids had a variable effect on which screening or treatment options were selected. Exposure to decision aids relative to controls resulted in a consistent non-significant trend toward reduced preference for major surgery over conservative options by 21 to 42 per cent in five of five studies; however, they had no impact on circumcision in two of two studies. For colon and prostate cancer screening choices, the results were inconsistent. Two studies have shown no impact on persistence with chosen option and few studies have shown significant benefits on general health outcomes (two of three studies), or disease-specific health outcomes (one of four studies). REVIEWER'S CONCLUSIONS: The number of decision aids is expanding, but there is considerable overlap in some areas leaving gaps in others. Trials of decision aids indicate that they are superior to usual care interventions in improving knowledge and realistic expectations of the benefits and harms of options; reducing passivity in decision making; and lowering decisional conflict stemming from feeling uninformed. When simpler versions of decision aids are compared to more detailed aids, the differences in knowledge are marginal but there are other benefits in terms of creating realistic expectations and in reducing decisional conflict. To date, decision aids have had little effect on anxiety or satisfaction with the decision making process or satisfaction with the decision. Their effects on choices vary with the decision. The effects on persistence with chosen therapies and health outcomes require further evaluation. The essential elements in decision aids for different groups and different types of decisions need to be established. Consensus needs to be reached regarding standards for developing and evaluating decision aids.

The origin of Palestinians and their genetic relatedness with other Mediterranean populations.

The genetic profile of Palestinians has, for the first time, been studied by using human leukocyte antigen (HLA) gene variability and haplotypes. The comparison with other Mediterranean populations by using neighbor-joining dendrograms and correspondence analyses reveal that Palestinians are genetically very close to Jews and other Middle East populations, including Turks (Anatolians), Lebanese, Egyptians, Armenians, and Iranians. Archaeologic and genetic data support that both Jews and Palestinians came from the ancient Canaanites, who extensively mixed with Egyptians, Mesopotamian, and Anatolian peoples in ancient times. Thus, Palestinian-Jewish rivalry is based in cultural and religious, but not in genetic, differences. The relatively close relatedness of both Jews and Palestinians to western Mediterranean populations reflects the continuous circum-Mediterranean cultural and gene flow that have occurred in prehistoric and historic times. This flow overtly contradicts the demic diffusion model of western Mediterranean populations substitution by agriculturalists coming from the Middle East in the Mesolithic-Neolithic transition.

The management of menopausal sequelae in patients with breast cancer.

The use of chemotherapy and tamoxifen for young women with breast cancer results in premature menopause in a significant number of patients. Early menopause has serious vasomotor, psychological, genitourinary, cardiac and skeletal effects. Psychopharmacological and herbal preparations are widely used for the treatment of vasomotor symptoms. The incidence of psychological and depressive illness following the menopause in women with breast cancer is significantly higher than seen with the natural menopause. Targeting this population of patients for early diagnosis and psychiatric intervention is recommended. Local vaginal moisturising or oestrogen cream would help to alleviate some of the urogenital symptoms. Patients whose treatment included Anthracycline chemotherapy or radiation to the heart and those with a history of heart disease, should be monitored closely for latecardiac complications. Early menopause is the major risk factor for the development of osteoporosis. Weight bearing exercise, bisphosphonate or calcitonin therapy are all useful in treating osteoporosis. Should a woman with a history of breast cancer be given hormone replacement therapy is one of the most controversial issues in the oncology field. There are no published prospective randomised studies on the subject. The available data suggests an increase of 5% of breast cancer related events when hormone replacement therapy is given to women with breast cancer. However, in certain situations, this could be given after a detailed explanation and documentation. The patient and physician should balance the severity of symptoms against the increased breast cancer related events and the final decision should be left to the patient.

Evidence of DNA repair/processing defects in cultured skin fibroblasts from breast cancer patients.

Cultured skin fibroblasts from 14 breast cancer (BC) patients were compared with those from 8 healthy subjects and 4 ataxia-telangiectasia (A-T) cases for sensitivity to low dose-rate (0.007 Gy/min) gamma-irradiation assessed by a colony-forming assay and for postirradiation DNA synthesis inhibition determined by the method of [(3)H]thymidine incorporation. Fibroblasts from all but two BC patients exhibited moderately enhanced radiosensitivity in the colony-forming assay, occupying an intermediate position between the controls and the A-T cases. Fibroblasts from the radiosensitive BC patients also showed an intermediate response with respect to radio-induced DNA synthesis inhibition compared with those from controls and A-T cases. In a host cell reactivation assay using an irradiated herpes simplex virus for plaque-forming ability, the fibroblasts from 7 BC patients, used as host cells, resulted in a significantly reduced (P < 0.0001) recovery of the virus relative to the 8 control fibroblasts, suggesting a deficiency in DNA repair in the former. A number of the BC fibroblasts analyzed in an assay for potentially lethal damage repair confirmed the repair deficiency in the fibroblasts from the BC patients. Defects in DNA repair and/or DNA processing after exposure to genotoxic agents would lead to genomic instability and hence would be responsible for cancer predisposition. Our data suggest that most BC patients may carry various genes resulting in such defects, and additional studies on normal cells from a larger cohort of BC patients and their family members are warranted to establish a connection between mutations or polymorphisms in specific DNA repair genes and susceptibility to breast cancer.

Polysubstituted pyrazoles, Part 4: Synthesis, antimicrobial and antiinflammatory activity of some pyrazoles.

As a continuation of an earlier interest in polysubstituted pyrazoles, the synthesis of some derivatives of 1H-pyrazol-4-yl-2-oxo-but-3-enoic acid and ethyl 4-hydroxy-1H-pyrazole-3-carboxylates of potential antimicrobial and antiinflammatory activity is described. One compound showed in vitro antibacterial activity and two compounds displayed in vivo antiinflammatory potency in rats.

Tumor lysis syndrome following hemi-body irradiation for metastatic breast cancer.

Tumor lysis syndrome (TLS) is a rare serious acute complication of cancer therapy, reported mainly following chemotherapy in patients with large tumor load and chemosensitive disease. These are mainly patients with non-Hodgkin's lymphoma, leukemia and rarely in solid tumors. It is less frequently described after radiotherapy for lymphoid and hematological malignancies. TLS following radiotherapy for solid tumors is a very rare complication. In this report/review we describe a seventy-three-year-old male patient with progressive metastatic carcinoma of the breast to the lungs, liver and bone. He was referred for radiotherapy because of generalized bony pains. The patient was planned for sequential hemi-body irradiation starting with the more symptomatic upper half body. After premedication, he was given 8.5 Gy to the mid point at the maximum chest separation with anterior lung attenuator limiting uncorrected lung dose to 6.15 Gy. A further 3.5 Gy electron boost to the fungating breast tumor was given to the 100%. Forty-eight hours after irradiation he developed hyperkalemia, hyperphosphatemia, hyperuricemia, hypocalcemia and renal failure. These clinical and biochemical changes are typical of tumor lysis syndrome (TLS). Despite hydration, and treating the hyperuricemia, the patient developed coma and died eight days after irradiation. The prophylaxis and management of TLS and in high-risk patients are described to avoid this frequently fatal complication.

Competitive binding to the oligopeptide binding protein, OppA: in-trap cleanup in an Fourier transform ion cyclotron resonance mass spectrometer.

This communication demonstrates that gentle infrared laser heating can remove unwanted buffer adducts from a gas-phase protein complex without dissociating the complex itself. Specifically, noncovalent complexes of the oligopeptide-binding protein, OppA, bound to either (Ala)3 or LysTrpLys were electrosprayed from aqueous buffer solution into a 9.4 tesla Fourier transform ion cyclotron resonance mass spectrometer. In addition to the intact complexes, several additional buffer adduct species were produced under the conditions of the experiment. Irradiation of the trapped ion population with a continuous-wave infrared CO2 laser at relatively low power (2.5 W) for 1 s dissociated the buffer adducts but retained the intact protein:peptide complexes. Adduct-free complex(es) were then readily identified, and signal-to-noise ratio also increased by an order of magnitude because the same number of protein ions are distributed over fewer species. Higher IR power (5 W for 1 s) dissociated the adduct-free complex(es) without internal fragmentation. The present in-trap clean-up technique may prove especially useful for identifying and screening the combinatorial library ligands most strongly bound to a receptor in the gas phase.

Observation of the noncovalent assembly and disassembly pathways of the chaperone complex MtGimC by mass spectrometry.

We have analyzed a newly described archaeal GimC/prefoldin homologue, termed MtGimC, by using nanoflow electrospray coupled with time-of-flight MS. The molecular weight of the complex from Methanobacterium thermoautotrophicum corresponds to a well-defined hexamer of two alpha subunits and four beta subunits. Dissociation of the complex within the gas phase reveals a quaternary arrangement of two central subunits, both alpha, and four peripheral beta subunits. By constructing a thermally controlled nanoflow device, we have monitored the thermal stability of the complex by MS. The results of these experiments demonstrate that a significant proportion of the MtGimC hexamer remains intact under low-salt conditions at elevated temperatures. This finding is supported by data from CD spectroscopy, which show that at physiological salt concentrations, the complex remains stable at temperatures above 65 degrees C. Mass spectrometric methods were developed to monitor in real time the assembly of the MtGimC hexamer from its component subunits. By using this methodology, the mass spectra recorded throughout the time course of the experiment showed the absence of any significantly populated intermediates, demonstrating that the assembly process is highly cooperative. Taken together, these data show that the complex is stable under the elevated temperatures that are appropriate for its hyperthermophile host and demonstrate that the assembly pathway leads exclusively to the hexamer, which is likely to be a structural unit in vivo.

Prevention of NSAID-induced gastroduodenal ulcers.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) are important agents in the management of arthritic and inflammatory conditions, and are among the most frequently prescribed medications in North America and Europe. However, there is overwhelming evidence linking these agents to a variety of gastrointestinal (GI) toxicities. OBJECTIVES: To review the effectiveness of common interventions for the prevention of NSAID induced upper GI toxicity. SEARCH STRATEGY: A literature search was conducted, according to the Cochrane methodology for identification of randomized controlled trials in electronic databases, including MEDLINE from 1966 to January 2000, Current Contents for 6 months prior to January 2000, Embase to Febuary 1999, and a search of the Cochrane Controlled Trials Register from 1973 to 1999. Recent conference proceedings were reviewed and content experts and companies were contacted. SELECTION CRITERIA: Randomized controlled clinical trials (RCTs) of prostaglandin analogues (PA), H2-receptor antagonists (H2RA) or proton pump inhibitors (PPI) for the prevention of chronic NSAID induced upper GI toxicity were included. DATA COLLECTION AND ANALYSIS: Two independent reviewers extracted data regarding population characteristics, study design, methodological quality and number of patients with endoscopic ulcers, ulcer complications, symptoms, overall drop-outs, drop outs due to symptoms. Dichotomous data was pooled using Revman V3.1. Heterogeneity was evaluated using a chi square test. MAIN RESULTS: Thirty-three RCTs met the inclusion criteria. All doses of misoprostol significantly reduced the risk of endoscopic ulcers. Misoprostol 800 ug/day was superior to 400 ug/day for the prevention of endoscopic gastric ulcers (RR=0.18, and RR=0.38 respectively, p=0.0055). A dose response relationship was not seen with duodenal ulcers. Misoprostol caused diarrhea at all doses, although significantly more at 800ug/day than 400ug/day (p=0.0012). Misoprostol was the only prophylactic agent documented to reduce ulcer complications. Standard doses of H2RAs were effective at reducing the risk of endoscopic duodenal (RR=0.24; 95% CI: 0.10-0.57) but not gastric ulcers(RR=0.73; 95% CI:0.50-1.09). Both double dose H2RAs and PPIs were effective at reducing the risk of endoscopic duodenal and gastric ulcers (RR=0.44; 95% CI:0.26-0.74 and RR=0.37;95% CI;0.27-0.51 respectively for gastric ulcer), and were better tolerated than misoprostol. REVIEWER'S CONCLUSIONS: Misoprostol, PPIs, and double dose H2RAs are effective at preventing chronic NSAID related endoscopic gastric and duodenal ulcers. Lower doses of misoprostol are less effective and are still associated with diarrhea. Only Misoprostol 800ug/day has been directly shown to reduce the risk of ulcer complications.

The prevention of chronic NSAID induced upper gastrointestinal toxicity: a Cochrane collaboration metaanalysis of randomized controlled trials.

OBJECTIVE: To review the effectiveness of common interventions for the prevention of nonsteroidal antiinflammatory drug (NSAID) induced upper gastrointestinal (GI) toxicity. METHODS: Randomized controlled clinical trials (RCT) of prostaglandin analogs, H2-receptor antagonists (H2RA), or proton pump inhibitors (PPI) for the prevention of chronic NSAID induced upper GI toxicity were identified through electronic databases, the Cochrane control trials register, conference proceedings, and by contacting content experts and companies. Outcome measures investigated were endoscopic ulcers, ulcer complications, symptoms, overall dropouts, dropouts due to symptoms, and study quality. RESULTS: Thirty-four RCT met the inclusion criteria. All doses of misoprostol significantly reduced the risk of endoscopic ulcers. Misoprostol 800 microg/day was superior to 400 microg/day for the prevention of endoscopic gastric ulcers (RR 0.18, RR 0.38, respectively; p = 0.0055). A dose-response relationship was not seen with duodenal ulcers. Misoprostol caused diarrhea at all doses, although significantly more at 800 than 400 microg/day (p = 0.0012). Misoprostol was the only prophylactic agent documented to reduce ulcer complications. Standard doses of H2RA were effective at reducing the risk of endoscopic duodenal (RR 0.24, 95% CI 0.10-0.57) but not gastric ulcers (RR 0.73, 95% CI 0.50-1.09). Both double dose H2RA and PPI were effective at reducing the risk of endoscopic duodenal and gastric ulcers (RR 0.44, 95% CI 0.26-0.74 and RR 0.37, 95% CI 0.27-0.51, respectively, for gastric ulcer) and were better tolerated than misoprostol. CONCLUSION: Misoprostol, PPI, and double dose H2RA are effective in preventing chronic NSAID related endoscopic gastric and duodenal ulcers. Lower doses of misoprostol are less effective and are still associated with diarrhea. Only misoprostol 800 microg/day has been directly shown to reduce the risk of ulcer complications.