The Atacama Rover Astrobiology Drilling Studies (ARADS) Project

With advances in commercial space launch capabilities and reduced costs to orbit, humans may arrive on Mars within a decade. Both to preserve any signs of past (and extant) martian life and to protect the health of human crews (and Earth's biosphere), it will be necessary to assess the risk of cross-contamination on the surface, in blown dust, and into the near-subsurface (where exploration and resource-harvesting can be reasonably anticipated). Thus, evaluating for the presence of life and biosignatures may become a critical-path Mars exploration precursor in the not-so-far future, circa 2030. This Special Collection of papers from the Atacama Rover Astrobiology Drilling Studies (ARADS) project describes many of the scientific, technological, and operational issues associated with searching for and identifying biosignatures in an extreme hyperarid region in Chile's Atacama Desert, a well-studied terrestrial Mars analog environment. This paper provides an overview of the ARADS project and discusses in context the five other papers in the ARADS Special Collection, as well as prior ARADS project results.

Sand dams for sustainable water management: Challenges and future opportunities

Sand dams are impermeable water harvesting structures built to collect and store water within the volume of sediments transported by ephemeral rivers. The artificial sandy aquifer created by the sand dam reduces evaporation losses relative to surface water storage in traditional dams. Recent years have seen a renaissance of studies on sand dams as an effective water scarcity adaptation strategy for drylands. However, many aspects of their functioning and effectiveness are still unclear. Literature reviews have pointed to a range of research gaps that need further scientific attention, such as river corridors and network dynamics, watershed-scale impacts, and interaction with social dynamics. However, the scattered and partially incomplete information across the different reviews would benefit from an integrated framework for directing future research efforts. This paper is a collaborative effort of different research groups active on sand dams and stems from the need to channel future research efforts on this topic in a thorough and coherent way. We synthesize the pivotal research gaps of a) unclear definition of "functioning" sand dams, b) lack of methodologies for watershed-scale analysis, c) neglect of social aspects in sand dam research, and d) underreported impacts of sand dams. We then propose framing future research to better target the synthesized gaps, including using the social-ecological systems framework to better capture the interconnected social and biophysical research gaps on sand dams, fully utilizing the potential of remote sensing in large-scale studies and collecting sand dam cases across the world to create an extensive database to advance evidence-based research on sand dams.

POS0984 PREVALENCE OF axSpA IN PATIENTS TREATED FOR CHRONIC BACK PAIN IN CHIROPRACTIC CLINICS: THE OREGON CHIROPRACTIC AXIAL SPONDYLOARTHRITIS STUDY (ORCAS) – AN INTERIM ANALYSIS

Background

Non-rheumatology settings such as chiropractor clinics, where chronic back pain (CBP; including chronic back, buttock, or hip pain) patients are first seen, lack consistency in referral of patients to rheumatologists where the underlying cause may be axial spondyloarthritis (axSpA).

Objectives

Primary objective was to estimate the prevalence of axSpA in CBP patients attending four chiropractic clinics in Portland, Oregon, referred to a rheumatology clinic using a referral strategy identifying features of spondyloarthritis (SpA).

Methods

Adults attending one of four chiropractor clinics between Nov 2020 and Nov 2021 for CBP starting before age of 45, without prior diagnosis of SpA were eligible for inclusion. Patients were referred to rheumatologist for diagnostic assessment via phone consultation, if they had inflammatory back pain (IBP) and/or ≥1 of the following features: a family history of SpA, inflammatory bowel disease (IBD), psoriasis, good response to non-steroidal anti-inflammatory drugs, history of heel pain, uveitis, or joint swelling. The subsequent rheumatology assessment included history, C-reactive protein, HLA-B27, x-ray and MRI of the sacroiliac joints. Based on the assessment, patients were categorized as radiographic axSpA, non-radiographic axSpA, peripheral SpA, or no SpA. Endpoints were summarized using descriptive statistics.

Results

A total of 3,103 visits were recorded at four chiropractic offices between Nov 2020 and Nov 2021. Top ten chief complaints are presented in Figure 1. In total, 115 patients were referred by the chiropractors and 84 patients were confirmed to be eligible. Of the 74 patients who provided consent, 59 (79.7%) had IBP, and 66 (89.2%) had at least one clinical SpA feature. At interim data lock, 63 patients were fully assessed by a rheumatologist, of which 7 (11.1%) were HLA-B27 positive and 24 (38.1%) had rheumatologist-evaluated IBP. Eight (12.7%) patients had SpA, 6 (9.5%) were diagnosed as axSpA and fulfilled Assessment of Spondyloarthritis International Society (ASAS) classification criteria, 1 (1.6%) patient was diagnosed as psoriatic arthritis without imaging evidence of axial involvement and fulfilled Classification Criteria for Psoriatic Arthritis, and 1 (1.6%) had undifferentiated peripheral SpA and fulfilled ASAS Classification Criteria.

Figure 1.

Chief complaints reported by patients at chiropractor visits (n=3103)

Conclusion

More than 10% of patients attending chiropractic clinics for musculoskeletal complaints had undiagnosed SpA conditions, with axSpA being the most common. Educational efforts targeted at chiropractors to suspect and refer appropriate cases to rheumatologists are needed.

Table 1.

Demographic and clinical characteristics stratified by diagnosis as confirmed by Rheumatologist

Radiographic axSpA (N = 1)Non-radiographic axSpA (N = 5)Peripheral SpA Including PsA (N= 2)No SpA (N = 55)Age, years (Mean; SD)73 (-)36.8 (6.4)46 (1.4)45.1 (12.1)Sex, Female – n (%)04 (80.0)2 (100)32 (58.2)Family history of spondyloarthritis, Yes – n (%)01 (20.0)1 (50.0)9 (16.4)Chronic back pain duration, years (Mean; SD)49 (-)12.4 (6.0)11 (7.0)15 (10.8)Confirmed during rheumatology visit – n (%) IBP* (4 out of 5 criteria as checked by patient)1 (100)3 (60.0)1 (50.0)27 (49.1) IBP* (4 out of 5 criteria per rheumatologist’s opinion)02 (40.0)022 (40.0) History of plantar fasciitis or Achilles tendinitis04 (80.0)2 (100)14 (25.5) History of peripheral joint swelling001 (50.0)8 (14.6) Positive response to NSAIDs1 (100)1 (20.0)2 (100)21 (38.2) Psoriasis1 (100)01 (50.0)2 (3.6) Inflammatory bowel disease0001 (1.9) Uveitis0001 (1.8) HLA-B27 positive02 (40.0)1 (50.0)4 (7.3) CRP, Above 10.0 mg/L02 (40.0)1 (50.0)1 (1.8) SI Joints X-ray positive for sacroiliitis (modified New York criteria)1 (100)001 (1.8) SI Joints MRI positive for active inflammation1 (100)3 (60.0)00

*According to the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for axSpA

Disclosure of Interests

Sonam Kiwalkar: None declared, Shireesh Bhalerao Consultant of: Eli Lilly and Company, Kim Phung Nguyen: None declared, Rose Quinn: None declared, Dave Perham: None declared, William Malatestinic Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Rebecca Bolce Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Theresa Hunter Employee of: Eli Lilly and Company, Pragya Khurana Consultant of: Eli Lilly and Company; ICON plc has received funding from several pharmaceutical companies involved in the marketing products for treatment of spondyloarthritis., Atul Deodhar Speakers bureau: Janssen, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Aurinia, Bristol Myers Squibb, Celgene, Eli Lilly, Glaxo Smith & Kline, Janssen, MoonLake, Novartis, Pfizer, UCB, Grant/research support from: AbbVie, Bristol Myers Squibb, Celgene, Eli Lilly, Glaxo Smith & Kline, Novartis, Pfizer, UCB

TOTAL risk score for predicting safe very early discharge in patients with ST-elevation myocardial infarction (STEMI)

Background/Introduction

Previously validated risk scores for identifying low-risk patients after ST-segment elevation myocardial infarction (STEMI) have led to acceptance of the safety and feasibility of discharge after 48–72 hours of hospitalization, reducing hospital length of stay and costs. With ongoing improvements in outcomes, it may be possible to select patients who are safe to discharge very early (24–48 hours) but this has never been evaluated.

Purpose

We sought to develop and validate a novel risk score for identifying low-risk patients suitable for very early discharge (≤48 hours of hospitalization) post-STEMI.

Methods

We derived a novel risk score using data from patients enrolled in the Trial of Routine Aspiration Thrombectomy with PCI versus PCI alone in Patients with STEMI (TOTAL). The TOTAL database was randomly divided into a derivation cohort with 2/3 of the composite events and non-events and remaining 1/3 as the internal validation cohort. Using the derivation cohort, we identified risk factors for cardiovascular death (CV) or non-fatal cardiac arrest by performing a univariate and multivariable stepwise regression analysis of baseline clinical and angiographic characteristics. Each co-variate was assigned an integer score based on regression coefficients and the novel TOTAL risk score was developed by adding points from each risk factor profile. We externally validated the TOTAL score using data from the Radial versus Femoral Access for Coronary Intervention (RIVAL) trial.

Results

The TOTAL derivation cohort included 6331 participants with 287 events (CV death/cardiac arrest). Twelve independent risk-factors associated with risk of CV death and non-fatal cardiac arrest at 1 year were selected and weighted for the TOTAL risk score (Table 1). In the TOTAL validation cohort (n=3166), patients with a TOTAL score of 0–4 points (n=779 (24.6%)) were categorized as very low risk with only a 0.1% risk of CV death/cardiac arrest observed within 24 hours of hospitalization, and no further events observed between 24 hours and 30 days post-STEMI. In the RIVAL validation dataset (n=1451), patients with a TOTAL score of 0–4 points (n=737 (50.7%)) had a 0.3% risk of CV death/cardiac arrest within 24 hours, with no further events observed between 24 hours and 72 hours of hospitalization.

Conclusion

The TOTAL risk score identified a very low risk subset of patients for whom early discharge, 24–48 hours post-STEMI, is likely safe. These findings have the potential to change practice and support early discharge after STEMI.

Funding Acknowledgement

Type of funding sources: None.

Non-inflammatory joint effusions as a presenting sign of hypothyroidism in a dog

Non-inflammatory joint effusion with characteristically increased synovial fluid viscosity is a rare but well-recognised rheumatic manifestation of hypothyroidism in people and based on the literature search, this is the first report of the condition in dogs. A 2-year-old Pyrenean Mountain dog presented for lameness and multiple joint effusions. CT confirmed effusions affecting multiple limb joints along with delayed closure of multiple physes. Synovial fluid analysis from the effused joints showed no evidence of inflammation but the fluid viscosity was markedly increased. Serum total thyroxine concentration was decreased, thyroid-stimulating hormone concentration was increased and antithyroglobulin autoantibody measurement returned a positive result. Oral levothyroxine supplementation resulted in relatively rapid and complete resolution of the clinical signs, in association with attaining a euthyroid state. Follow-up examination and CT six months later confirmed resolution of the joint effusions and significant improvement or resolution of the other documented skeletal changes.

The 2020 report of The Lancet Countdown on health and climate change: responding to converging crises

For the Chinese, French, German, and Spanish translations of the abstract see Supplementary Materials section.

Quantifying the performance of dual-use rainwater harvesting systems

Rainwater harvesting systems in urban settings are increasingly relied upon to mitigate pluvial flooding on top of providing an additional water supply. Alternative designs have been proposed to support their dual use. Stormwater management performance is typically evaluated through long-term averages. However, long-term assessment is not aligned with the goal of attenuating the impacts of short duration high-intensity rainfall events. This paper contributes a framework for evaluating the dual-use performance of design alternatives. The framework incorporates a set of stormwater management metrics that provides a robust characterisation of performance during significant rainfall events. To the usual long-term volumetric retention metric, we add: 1) metrics that represent the total volume and duration above predevelopment (greenfield) runoff rates; and 2) robust peak outflow rate and retention efficiencies based on the long-term median of a representative sample of significant rainfall events. Our multi-criteria performance visualisations of alternative dual-use designs highlight the importance of carefully designing the forecast-based controlled release mechanisms built into active systems. This work has direct implications for design guidance standards, which we discuss.

The Water Footprint of Diets: A Global Systematic Review and Meta-analysis

Agricultural water requirements differ between foods. Population-level dietary preferences are therefore a major determinant of agricultural water use. The "water footprint" (WF) represents the volume of water consumed in the production of food items, separated by water source; blue WF represents ground and surface water use, and green WF represents rain water use. We systematically searched for published studies using the WF to assess the water use of diets. We used the available evidence to quantify the WF of diets in different countries, and grouped diets in patterns according to study definition. "Average" patterns equated to those currently consumed, whereas "healthy" patterns included those recommended in national dietary guidelines. We searched 7 online databases and identified 41 eligible studies that reported the dietary green WF, blue WF, or total WF (green plus blue) (1964 estimates for 176 countries). The available evidence suggests that, on average, European (170 estimates) and Oceanian (18 estimates) dietary patterns have the highest green WFs (median per capita: 2999 L/d and 2924 L/d, respectively), whereas Asian dietary patterns (98 estimates) have the highest blue WFs (median: 382 L/d per capita). Foods of animal origin are major contributors to the green WFs of diets, whereas cereals, fruits, nuts, and oils are major contributors to the blue WF of diets. "Healthy" dietary patterns (425 estimates) had green WFs that were 5.9% (95% CI: -7.7, -4.0) lower than those of "average" dietary patterns, but they did not differ in their blue WFs. Our review suggests that changes toward healthier diets could reduce total water use of agriculture, but would not affect blue water use. Rapid dietary change and increasing water security concerns underscore the need for a better understanding of the amount and type of water used in food production to make informed policy decisions.

Phase IB study of the combination of docetaxel, gemcitabine, and bevacizumab in patients with advanced or recurrent soft tissue sarcoma: the Axtell regimen

BACKGROUND

To assess the response of patients with soft tissue sarcoma (STS) to the combination of docetaxel, bevacizumab, and gemcitabine. Vascular endothelial growth factor (VEGF)-A levels and expression of VEGF-A and VEGF receptors 1 and 2 were evaluated.

PATIENTS AND METHODS

Thirty-eight chemotherapy-naive patients with STS were enrolled. A dose-finding study for gemcitabine from 1000, 1250, then 1500 mg/m(2) was done in nine patients (three cohorts), followed by an expansion cohort of 27 patients. Dose of docetaxel was 50 mg/m(2), bevacizumab was 5 mg/kg, and gemcitabine was 1500 mg/m(2), every 2 weeks. Serum VEGF-A was measured by enzyme-linked immunosorbent assay and tissue VEGF-A and its receptors by immunohistochemistry.

RESULTS

The median follow-up was 36 months. The overall response rate observed was 31.4%, with 5 complete and 6 partial responses, and 18 stable diseases lasting for a median of 6 months. There was no significant hematologic toxicity. The adverse events with the highest grade were attributed to bevacizumab. There was no correlation of VEGF pathway biomarkers with outcome.

CONCLUSIONS

The combination of gemcitabine, docetaxel, and bevacizumab is safe and effective in patients with STS. The most concerning adverse events were consequences of bevacizumab administration. The benefit of bevacizumab in this patient population remains unclear.

Influence of the concentration of CO2 and SO2 on the absorption of CO2 by a lithium orthosilicate-based absorbent

A novel, high temperature solid absorbent based on lithium orthosilicate (Li(4)SiO(4)) has shown promise for postcombustion CO(2) capture. Previous studies utilizing a clean, synthetic flue gas have shown that the absorbent has a high CO(2) capacity, >25 wt %, along with high absorption rates, lower heat of absorption and lower regeneration temperature than other solids such as calcium oxide. The current effort was aimed at evaluating the Li(4)SiO(4) based absorbent in the presence of contaminants found in typical flue gas, specifically SO(2), by cyclic exposure to gas mixtures containing CO(2), H(2)O (up to 25 vol. %), and SO(2) (up to 0.95 vol. %). In the absence of SO(2), a stable CO(2) capacity of ∼ 25 wt % over 25 cycles at 550 °C was achieved. The presence of SO(2), even at concentrations as low as 0.002 vol. %, resulted in an irreversible reaction with the absorbent and a decrease in CO(2) capacity. Analysis of SO(2)-exposed samples revealed that the absorbent reacted chemically and irreversibly with SO(2) at 550 °C forming Li(2)SO(4). Thus, industrial application would require desulfurization of flue gas prior to contacting the absorbent. Reactivity with SO(2) is not unique to the lithium orthosilicate material, so similar steps would be required for other absorbents that chemically react with SO(2).

Prevalence and cognitive impact of cerebrovascular findings in Alzheimer's disease: a retrospective, naturalistic study

AIMS

Cerebrovascular disease (CVD) is a major risk factor for cognitive decline associated with progression to Alzheimer's disease (AD) and dementia. The objective of this study was to retrospectively assess the prevalence of CVD and its cognitive impact in patients with AD in everyday clinical practice.

METHODS

Medical notes were retrospectively reviewed for all individuals who presented at East Sussex Memory Clinic (2004-2008) for investigation of cognitive impairment and had brain magnetic resonance imaging (MRI) as part of their clinical work-up. Global cognitive status was assessed with Mini-Mental State Examination (MMSE) and Cambridge Cognitive Examination. The extent of cerebrovascular abnormalities was qualitatively evaluated with MRI.

RESULTS

Notes were reviewed for 232 patients (109 males, 123 females), mean age 76 years (range 62-93), who underwent MRI. Of these, 167 (72%) patients were diagnosed with AD. CVD was present in 89% of AD patients and 47% of patients had moderate to severe cerebrovascular abnormalities. The majority of patients (57%) had MMSE scores in the 21-26 range, indicative of mild AD. There was a trend towards worse cognitive status in patients with more severe CVD, which did not reach significance. Hachinski Ischaemic score indicated these patients did not have vascular dementia (VaD) (mean +/- standard deviation 1.1 +/- 1.3).

CONCLUSION

These findings, based on qualitative MRI, indicate that cerebrovascular pathology is a very common associated feature in patients with mild to moderate AD, without VaD. Although the study suggests that CVD does not contribute to cognitive decline, and is not associated with the development of VaD, a non-significant trend was observed towards worsening cognitive status with increasing severity of CVD. The finding of this trend suggests a need for additional research, especially a prospective quantitative method of assessing CVD, to improve our understanding of how CVD contributes to cognitive impairment in AD.

Phase I/II study of docetaxel (D), gemcitabine (G), and bevacizumab (B) in patients (pts) with advanced or recurrent soft tissue sarcoma (STS)

10056

Background: The combination of G and D has shown efficacy against refractory STS (Hensley, JCO 2002). STS have a high content of VEGF, which is associated with poor prognosis. This phase I/II study assesses the safety, tolerability, efficacy, and pharmacodynamics (PD) of B in combination with G+D, given on a two-weekly schedule to minimize adverse events (AEs). We are reporting the phase I results. Methods: Untreated pts with advanced or recurrent STS and ECOG PS =2 were eligible. Some pts were treated in a neoadjuvant setting, when surgically appropriate. Planned doses were G 1,000, 1,250, and 1,500 mg/m2, D 50 mg/m2, and B 5 mg/kg iv, every 2 wks. G doses were escalated in serial pt cohorts to determine the maximum tolerated dose (MTD) of G with fixed doses of D and B. MTD was assessed on the first 2 cycles (1 cycle = 2 wks). Treatment was continued until progression or unacceptable toxicity. For neoadjuvant therapy, B was given only for 4 cycles, followed by 4 cycles without B in anticipation of surgery and pts came off study at that point. PD and antitumor efficacy were also assessed. Results: Nine pts have been treated on the phase I escalation arm, including 3 in the neoadjuvant setting. There were no dose limiting toxicities. After 4 cycles with G at 1,500 mg/m2, there was 1 asymptomatic grade 4 bowel perforation at the site of the tumor in a pt with initially inoperable leiomyosarcoma (LMS). After emergency surgery, the pt is free of disease. Observed grade 1 and 2 AEs include alopecia, diarrhea, fatigue (5 each), rigors (4), nausea, dyspnea, headaches (3 each), chest pain, epistaxis, stomatitis, anemia (2 each), rash, hypertension, neuropathy, leukopenia (1 each). There were 1 CR (angiosarcoma), 2 PR, (myxoid sarcoma, undifferentiated sarcoma), 4 NC (2 LMS, liposarcoma, PNST), and 2 PD (myxoid sarcoma, PNST). Necrosis was observed, including in NC disease. Three pts are free of disease after surgery. Conclusions: The combination of G, D, and B given every 2 weeks is safe and has demonstrated some activity in pts with advanced or recurrent STS. The phase II arm is ongoing at G 1,500 mg/m2 with 4 pts already enrolled. Mature data including PD will be reported at the meeting.

No significant financial relationships to disclose.

Pilot study of selective internal radiation therapy (SIRT) for patients with unresectable neuroendocrine liver metastases (NETLM)

15096

Background: Few effective treatment options exist for inoperable NETLM. A prospective single-unit study assessed safety and efficacy of radioactive yttrium90 resin (SIR) in 34 patients with unresectable (NETLM). Method: Microspheres were administered via temporary percutaneous hepatic artery catheter with concomitant 7day 5-flurouracil infusion. Patients were monitored prospectively and treatment response measured by CT imaging and chromogranin A (CgA). Results: 34 patients (22 male), mean age 61 years (range 32–79) were treated with SIRT from December 2003 to December 2005. Mean follow-up 28.9 months, (95% CI 23.4 to 32.3). Complications were: post-embolitic pain and lethargy 1 week-1 month; 3 radiation gastritis, 2 of whom developed a duodenal ulcer. RECIST response on CT scan of 34 patients at 1 month: PR 9 (26%); SD 22 (65%); PD 3 (9%); 32 at 6 months, PR 7 (22%); SD 19 (59%); PD 6 (19%); 29 at 12 months CR 2 (7%); PR 3 (10%); SD 16 (55%); PD 8 (28%); 16 at 18 months, CR 4(25%); PR 1 (6%); SD 8 (50%); PD =3 (19%); 8 at 24 months, CR 4 (50%);SD 2 (25%),PD 2 (25%); 6 at 30 months, CR 2 (33%); SD 2 (33%); PD 2 (33%). CgA U/L fall from entry was: 19 (26%) at one month; 15 (43%) at 6 months; 15 (52%) at 9 months; 11 (57%) at 12 months; 8 (38%) at 24 months and 4 (80%) at 30 months. At 36 months from entry 11 (32%) have died; 8 (24%) have PD; 9 (26%) have SD and 6 (18%), (15 to 30 months) have CR on CT scan. Conclusion: SIRT is a promising treatment option for patients with in-operable NETLM.

No significant financial relationships to disclose.

Gastric bypass model in the obese rat to study metabolic mechanisms of weight loss

A rat model replicating gastric bypass with Roux-en-Y (GB) as used in morbidly obese patients, evolved in our laboratory in stages, using the Zucker rat as an obese model (GB) is presented. In the final model, a 20% gastric fundic pouch to limit the gastric reservoir was created using two staple lines (Ethicon). A 4- to 5-mm end-to-side gastrojejunostomy and a 6- to 8-mm jejunojejunostomy, at 10 cm length of the Roux-en-Y limb, placed 16 cm below the ligament of Treitz, was hand sewn to create a limited area of nutrient digestion and absorption. Controls underwent sham operation. Rats were divided into: (i) sham-op ad lib-fed (Control); (ii) GB; and (iii) sham-op pair fed (PF) in two experiments. In Experiment 1, 24 Zuckers (control n = 8; GB n = 8; PF n = 8) were studied to assess the effectiveness of the model for weight loss. In Experiment 2, 24 Zuckers (8/group) were studied to confirm the effects of the operation on weight loss and on metabolic parameters. Boost was given for 4 days starting 24 h postop and then ground chow was given. Daily food intake (FI), meal size (MZ), meal number (MN), and body weight (BW) were measured. Rats were sacrificed on Day 20 in Experiment 1 and on Day 10 in Experiment 2. Serum metabolites and body fat weight were measured. Data were evaluated using Student's t test. Controls steadily gained BW (5.2-6.1 g/day), reaching approximately 500 g. In GB: FI, MZ, MN, BW, glucose, free fatty acids, insulin, and body fat decreased (P < 0.05). In PF: BW, insulin, triglycerides, and body fat decreased. A dependable, reproducible gastric bypass with Roux-en-Y obesity model was developed. This permits the study of biochemical and eventually molecular mechanism(s) of weight loss resulting from the operation.

Intra-operative quality assessment of coronary artery bypass grafts

Early coronary artery bypass graft (CABG) failure is a troubling complication that may result in a wide range of problems, including refractory angina, myocardial infarction, low cardiac output, arrhythmia, and fatal heart failure. Early graft failures are related to poor quality and size of the distal native vascular bed, coagulation abnormalities, or technical problems involving the graft conduits and anastomoses. Unfortunately, graft failure is difficult to detect during surgery by visual assessment, palpation, or conventional monitoring. We evaluated the accuracy and utility of a transit-time, ultrasonic flow measurement system for measurement of CABGs. There were no differences between transit-time measurements and volumetric-time collected samples in an in vitro circuit over a range of flows from 10 to 100ml/min (Bland and Altman Plot, 1.96 SD). Two hundred and ninety-eight CABGs were examined in 125 patients. Graft flow rate was proportional to the target vessel diameter. Nine technical errors were detected and corrected. Flow waveform morphology provided valuable information related to the quality of the anastamosis, which led to the immediate correction of technical problems at the time of surgery.

Integrating public health into medical education: community health projects in a Primary Care Preceptorship

Physicians must integrate care of populations with the care of individual patients to function optimally in today's health care environment. With this understanding, medical school curricula are increasingly addressing the skills and knowledge of public health along with those of clinical medicine. The University of Utah School of Medicine in 1997 revised its four-year curriculum to increase the teaching of topics needed by future physicians, including public health. This report describes one course in the curriculum, the Primary Care Preceptorship (PCP), a fourth-year, six-week required rotation that assists students in learning about the health needs of a community along with providing primary care for its individual residents. Students in the PCP spend approximately 60% of their time in clinical primary care and 40% completing a community health project. In the first year of the PCP, 32 students completed projects on clinical problems, 27 on community health needs assessment, 26 on patient education, and 15 on epidemiology.

CREB regulates hepatic gluconeogenesis through the coactivator PGC-1

When mammals fast, glucose homeostasis is achieved by triggering expression of gluconeogenic genes in response to glucagon and glucocorticoids. The pathways act synergistically to induce gluconeogenesis (glucose synthesis), although the underlying mechanism has not been determined. Here we show that mice carrying a targeted disruption of the cyclic AMP (cAMP) response element binding (CREB) protein gene, or overexpressing a dominant-negative CREB inhibitor, exhibit fasting hypoglycaemia [corrected] and reduced expression of gluconeogenic enzymes. CREB was found to induce expression of the gluconeogenic programme through the nuclear receptor coactivator PGC-1, which is shown here to be a direct target for CREB regulation in vivo. Overexpression of PGC-1 in CREB-deficient mice restored glucose homeostasis and rescued expression of gluconeogenic genes. In transient assays, PGC-1 potentiated glucocorticoid induction of the gene for phosphoenolpyruvate carboxykinase (PEPCK), the rate-limiting enzyme in gluconeogenesis. PGC-1 promotes cooperativity between cyclic AMP and glucocorticoid signalling pathways during hepatic gluconeogenesis. Fasting hyperglycaemia is strongly correlated with type II diabetes, so our results suggest that the activation of PGC-1 by CREB in liver contributes importantly to the pathogenesis of this disease.

Predicting the risk of death from heart failure after coronary artery bypass graft surgery

Heart failure is the most common cause of death among coronary artery bypass graft (CABG) patients. In addition, most variation in observed mortality rates for CABG surgery is explained by fatal heart failure. The purpose of this study was to develop a clinical risk assessment tool so that clinicians can rapidly and easily assess the risk of fatal heart failure while caring for individual patients. Using prospective data for 8,641 CABG patients, we used logistic regression analysis to predict the risk of fatal heart failure. In multivariate analysis, female sex, prior CABG surgery, ejection fraction <40%, urgent or emergency surgery, advanced age (70-79 yr and >80 yr), peripheral vascular disease, diabetes, dialysis-dependent renal failure and three-vessel coronary disease were significant predictors of fatal postoperative heart failure. A clinical risk assessment tool was developed from this logistic regression model, which had good discriminating characteristics (receiver operating characteristic clinical source = 0.75, 95% confidence interval: 0.71, 0.78).

IMPLICATIONS

In contrast to previous cardiac surgical scoring systems that predicted total mortality, we developed a clinical risk assessment tool that evaluates risk of fatal heart failure. This distinction is relevant for quality improvement initiatives, because most of the variation in CABG mortality rates is explained by postoperative heart failure.

How do General Practitioners learn of their patient's deaths?

OBJECTIVES

To investigate the methods by which General Practitioners learn, or do not learn, of their patients deaths, when the deaths occur in an institution in which the General Practitioner has no direct role in their care.

DESIGN

Using a semi-structured telephone questionnaire the relevant General Practitioners were asked of the method, if any, by which they had learned of their patients deaths, and their views on this.

SETTING

Sligo, Ireland.

RESULTS

In 6 (16%) of the 37 cases, the GP was informed of the death within one working day by hospital staff. In 22 (59%) of the cases, the GP had learned of the death through other means. In 9 (26%) of the cases the GP had not learned of the death. In 28 (75%) of the cases, the GPs were dissatisfied with either the fact that they did not know of the death, or even if they did know, the method by which they learned of the patients death.

CONCLUSION

General Practitioners, for a variety of reasons, wish to learn of their patient's deaths within a short length of time of such deaths occurring. When deaths occur in an institution in which the GP has no direct role in the care of their patients, the information is not forwarded to the GP within a reasonable length of time in the vast majority of cases. Such institutions need to realise the importance of this simple act, and to make it routine to forward the information.

Complete structural characterisation of the mammalian and Drosophila TRAF genes: implications for TRAF evolution and the role of RING finger splice variants

The complete murine TRAF2 gene was obtained using a lambda phage and PCR cloning strategy. The gene was found to consist of ten coding and one 5' non-coding exon spread over 28 kbp of DNA. We also report the basic structure of the human TRAF5 and TRAF6 genes obtained by analysis of the genomic DNA database. Comparison of these three gene structures, along with those previously described for TRAF1, TRAF3 and TRAF4, revealed the evolutionary relationship between the six known mammalian TRAFs. The TRAF1/TRAF2 and TRAF3/TRAF5 gene pairs were found to have arisen from recent independent gene duplications and to share a common ancestral gene. Specific TRAF4 and TRAF6 precursor genes were found to have arisen earlier during evolution, with the divergence of the TRAF6 precursor occuring earliest of all. The Drosophila genome was found to contain three TRAF family genes: dTRAF1, dTRAF6 (dTRAF2) and a previously undescribed member we have designated dTRAF3. TRAF-C domain homology indicated that dTRAF3 is likely to have derived from the common precursor for the TRAF 1, 2, 3 and 5 genes, whilst dTRAF1 and dTRAF6 have derived from the TRAF4 and TRAF6 precursor genes, respectively. The implication of these results for the functional evolution of TRAFs is discussed. Analysis is also presented of the conservation of the TRAF2A molecule, a TRAF2 alternate splice isoform with an extended RING finger domain previously described in mice. TRAF2A was not found to be encoded by the human or rat TRAF2 genes and no other murine TRAF gene was found to produce a similar alternate splice product. We also report that the sequence of murine C57BL/6 TRAF4 differs significantly from the published murine TRAF4 sequence, but appears to represent the actual TRAF4 sequence expressed in many mouse strains.

Improved stable isotope dilution-gas chromatography-mass spectrometry method for serum or plasma free 3-hydroxy-fatty acids and its utility for the study of disorders of mitochondrial fatty acid beta-oxidation

BACKGROUND

Disorders of fatty acid oxidation (FAO) are difficult to diagnose, primarily because in many of the FAO disorders measurable biochemical intermediates accumulate in body fluids only during acute illness. Increased concentrations of 3-hydroxy-fatty acids (3-OH-FAs) in the blood are indicative of FAO disorders of the long- and short-chain 3-hydroxy-acyl-CoA dehydrogenases, LCHAD and SCHAD. We describe a serum/plasma assay for the measurement of 3-OH-FAs with carbon chain lengths from C(6) to C(16).

METHODS

We used stable isotope dilution gas chromatography-mass spectrometry (GC-MS) with electron impact ionization and selected ion monitoring. Natural and isotope-labeled compounds were synthesized for the assay.

RESULTS

The assay was linear from 0.2 to 50 micromol/L for all six 3-OH-FAs. CVs were 5-15% at concentrations near the upper limits seen in healthy subjects. In 43 subjects, the medians (and ranges) in micromol/L were as follows: 3-OH-C(6), 0.8 (0.3-2.2); 3-OH-C(8), 0.4 (0.2-1.0); 3-OH-C(10), 0.3 (0.2-0.6); 3-OH-C(12), 0.3 (0.2-0.6); 3-OH-C(14), 0.2 (0.0-0.4); and 3-OH-C(16), 0.2 (0.0-0.5). 3-OH-FAs were increased in infants receiving formula containing medium chain triglycerides. Two patients diagnosed with LCHAD deficiency showed marked increases in 3-OH-C(14) and 3-OH-C(16) concentrations. Two patients diagnosed with SCHAD deficiency showed increased shorter chain 3-OH-FAs but no increases in 3-OH-C(14) to 3-OH-C(16).

CONCLUSION

Measuring blood concentrations of the 3-OH-FAs with this assay may be a valuable tool for helping to rapidly identify deficiencies in LCHAD and SCHAD and may also provide useful information about the status of the FAO pathway.

How much of a general practitioner's prescribing is outside his/her control?

OBJECTIVE

To analyse and quantify that portion of one General Practioner's prescribing that is outside his/her control.

DESIGN

Detailed analysis of one General Practioner's General Medical Services prescribing over a three month period during 1996.

SETTING

A Group Practice in Sligo, Ireland.

MAIN OUTCOME MEASURES

The number and cost of items outside the General Practitioner's control expressed as a percentage of his total General Medical Services prescribing. The source of these items, and whether they are newly prescribed items or not.

RESULTS

12.8% numerically and 23.8%, costwise, of items prescribed by one GMS General Practitioner were found to be outside his control. Of these items, psychiatric outpatient consultations and medical in-patient discharges account for 22.8% and 18.4% numerically, respectively, and 25.7% and 22.6% costwise, respectively of the total numbers of items and costs outside his control.

CONCLUSIONS

A relatively small proportion of items of a General Practitioners prescribing accounting for a disproportionately large amount of the costs are outside his control.

Use of the internal mammary artery graft in Northern New England. Northern New England Cardiovascular Disease Study Group

BACKGROUND

There is evidence that patients who receive an internal mammary artery graft (IMA) during coronary artery bypass surgery have increased long-term survival. However, an IMA is not used in all patients.

METHODS AND RESULTS

We studied the use of IMA grafts among 7944 patients undergoing initial, isolated coronary artery bypass surgery in Maine, New Hampshire, and Vermont from 1992 to 1995. Overall, the IMA graft was used in 82% of patients; of these, 97.2% had left IMA grafts. The use of the IMA graft varied considerably by patient and disease factors. Women received an IMA graft significantly less often (76% versus 85% in men, P<.01). Older patients (> or =75 years) were less likely to receive an IMA graft (67% versus 86%, P<.001). Smaller BSA was also associated with lower rates of IMA grafts in both sexes; however, men and women with BSA <1.8 m2 received an IMA graft at about the same rate. In general, more sick and more urgent patients had lower rates of IMA use. Patients with left ventricular ejection fraction <40% received an IMA less often than those with an ejection fraction > or =60% (77% versus 85%, P<.01). Patients with a greater number of diseased coronary vessels received an IMA more often (one, 78%; two, 82%; three, 85%). IMA use varied significantly by priority of surgery, with elective patients receiving an IMA 88% of the time, urgent 83%, and emergent 51% (Ptrend<.01). The use of the IMA graft varied from 42% to 95% among individual surgeons. Surgeons were consistent in their patterns of IMA graft use for specific risk groups. All surgeons had lower rates of IMA use among older patients, lower rates of IMA among women, and lower rates of IMA use among emergent or urgent patients. However, "low-use" surgeons had consistently lower rates of use within these patient groups. The overall rate of IMA graft use increased from 76% in 1992 to 86% in 1995 (Ptrend<.001). IMA graft use increased in all five centers and in all patient subgroups. The largest increases in use were seen among women (from 69% to 83%), among patients older than 75 years (from 55% to 75%), and in emergent patients (from 40% to 72%).

CONCLUSIONS

This regional prospective study of IMA graft use in initial coronary artery bypass surgery describes substantial variability in patient groups receiving an IMA as well as increasing IMA graft use over time. It also suggests that the practice patterns of surgeons are an important determinant of IMA use. These data indicate that even more patients could benefit from the use of this technique.