Nanosilver/DCOIT-containing surface coating effectively and constantly reduces microbial load in emergency room surfaces.

BACKGROUND: Colonization of near-patient surfaces in hospitals plays an important role as a source of healthcare-associated infections. Routine disinfection methods only result in short-term elimination of pathogens. AIM: To investigate the efficiency of a newly developed antimicrobial coating containing nanosilver in long-term reduction of bacterial burden in hospital surfaces to close the gap between routine disinfection cycles. METHODS: In this prospective, double-blinded trial, frequently touched surfaces of a routinely used treatment room in an emergency unit of a level-I hospital were treated with a surface coating (nanosilver/DCOIT-coated surface, NCS) containing nanosilver particles and another organic biocidal agent (4,5-dichloro-2-octyl-4-isothiazolin-3-one, DCOIT), whereas surfaces of another room were treated with a coating missing both the nanosilver- and DCOIT-containing ingredient and served as control. Bacterial contamination of the surfaces was examined using contact plates and liquid-based swabs daily for a total trial duration of 90 days. After incubation, total microbial counts and species were assessed. FINDINGS: In a total of 2880 antimicrobial samples, a significant reduction of the overall bacterial load was observed in the NCS room (median: 0.31 cfu/cm2; interquartile range: 0.00-1.13) compared with the control coated surfaces (0.69 cfu/cm2; 0.06-2.00; P < 0.001). The nanosilver- and DCOIT-containing surface coating reduced the relative risk of a critical bacterial load (defined as >5 cfu/cm2) by 60% (odds ratio 0.38, P < 0.001). No significant difference in species distribution was detected between NCS and control group. CONCLUSION: Nanosilver-/DCOIT-containing surface coating has shown efficiency for sustainable reduction of bacterial load of frequently touched surfaces in a clinical setting.

[Patient consent for the TraumaRegistry DGU based on the GDPR-A challenge for the hospitals: status quo and solution strategies]. / Patienteneinwilligungen für das TraumaRegister DGU® aufgrund der EU-Datenschutz-Grundverordnung (EU-DSGVO) ­ Eine Herausforderung für die Kliniken: Status quo und Lösungsstrategien.

According to the General Data Protection Regulation (GDPR 05/2018), anonymized data sets with a sufficiently high data density are classified as traceable and require a declaration of consent if they are evaluated centrally for research or quality control purposes. Quality assurance and further increases in the quality of care are, however, only possible with a nearly complete survey of seriously injured persons in the sense of health services research. The more than 600 German clinics that take part in the TraumaRegistry DGU® try to obtain the declarations of consent from this special patient population. The study clinic evaluated the rate of consent and the reasons for rejection or failure to obtain consent over a 12-month period. While using a resource-intensive workflow especially for patient education and obtaining the consent, a patient consent rate of 64.5% and an error rate of 35.5% were recorded. Of the 276 potential TraumaRegistry DGU® data records 98 could not be entered and were therefore neither available for quality control nor for multiple trauma research. In order to guarantee the quality control and the further improvement of the quality of care, an approximate total recording of the patient population is necessary; however, this cannot be achieved by requiring a declaration of consent. We therefore advocate creating the possibility of collecting the TraumaRegistry data set without consent, as this ultimately represents a standard data set, comparable to the Hospital Remuneration Act (§21-KHEntgG) data set but pseudonymised.

The impact of pay-for-performance on the quality of care in ophthalmology: Empirical evidence from Germany.

BACKGROUND: Pay-for-performance (P4P) has become a popular approach to increase effectiveness and efficiency in healthcare. So far, there is little evidence regarding the potential of P4P in the German healthcare setting. The aim of this study was to determine the impact of P4P on the quality of care in cataract surgery. METHODS: In 2012, a P4P program was implemented in a German surgical centre for ophthalmology. Five quality measures regarding process quality, outcomes, and patient satisfaction were measured over a period of 4.5 years. The P4P scheme consisted of bonus and penalty payments accounting for five per cent of total compensation. Overall, 1657 P4P cases were examined and compared with 4307 control cases. Interrupted time series and group comparisons were conducted to identify quality and spill-over effects. RESULTS: We found a positive impact on process quality and patient satisfaction before the implementation of the P4P scheme, but declining trends during and after the implementation. Our findings did not show an impact of P4P on outcome measures. Furthermore, P4P did not result in better quality of care, compared with the German hospital-based reimbursement scheme. CONCLUSION: This study did not show any positive long-term effects of the implementation of P4P on quality of care. Therefore, our results do not support the hypothesis that P4P leads to significant improvements in quality of care.

A template for broad consent in biobank research. Results and explanation of an evidence and consensus-based development process.

BACKGROUND: Biobanks increasingly presume long-term storage of biomaterials and data that shall be used for future research projects which are today unspecified. Appropriate consent documents for sample donors must therefore explain the breadth of consent and other elements of the biobank governance framework. Recent reviews demonstrated high variability in what issues these documents mention or not and how the issues are explained. This might undermine the protection of sample donors, complicate networked biobank research, create research waste and impact on public trust. METHODS: A systematic analysis of international research guidelines and existing broad consent templates was performed. Based on this information an interdisciplinary expert group from the AKMEK (Permanent Working Party of German RECs) developed a draft template and organized a comprehensive stakeholder consultation. After revision the final template was consented by all 53 German RECs. RESULTS: This paper briefly explores the spectrum of potentially relevant issues for broad consent forms. It then elaborates the template and how it was designed to be applicable in different types of biobanks. DISCUSSION: To further improve the validity and applicability of broad consent forms in biobank and other big data research, practice evaluations are needed. We hope that in this regard the presented template supports the development of new consent forms as well as the evaluation and revision of existing ones.

Screening for low aquatic bioaccumulation (2): physico-chemical constraints.

Physico-chemical properties related to the bioavailability of xenobiotics in aquatic environments have been tested for their ability to identify chemicals with low bioconcentration potential. Cut-offs in lipophilicity (log K(OW) < 3 or > 10), solubility and volatility (log Henry constant <-11 [atm (mol L(-1))(-1)]), degradability (ready biodegradability, hydrolysis) and ionisation (>5% ionisation at pH 7) have been adopted and combined into a decision tree based on 382 industrial chemicals. The five-parameter classification scheme was externally validated with 49 pesticides and successfully confirmed with 83 bioaccumulative compounds. The applicability domain of the model has been described in terms of chemical classes (excluding polybrominated compounds (>4 Br), organometallics, compounds with perfluorinated fragments, substances with an acyclic alkyl moiety (chain length > C7) and thiols) and ranges of physico-chemical properties. The present tool allows to securely de-prioritize more than 50% chemicals of low concern with regard to the B criterion (BCF < 2000). Bioassays with compounds with these physico-chemical constraints may be waived because testing may be technically not possible and does not appear scientifically necessary in persistent, bioaccumulative, toxic (PBT) substances and risk assessments.

Darwin--a mission to detect and search for life on extrasolar planets.

The discovery of extrasolar planets is one of the greatest achievements of modern astronomy. The detection of planets that vary widely in mass demonstrates that extrasolar planets of low mass exist. In this paper, we describe a mission, called Darwin, whose primary goal is the search for, and characterization of, terrestrial extrasolar planets and the search for life. Accomplishing the mission objectives will require collaborative science across disciplines, including astrophysics, planetary sciences, chemistry, and microbiology. Darwin is designed to detect rocky planets similar to Earth and perform spectroscopic analysis at mid-infrared wavelengths (6-20 mum), where an advantageous contrast ratio between star and planet occurs. The baseline mission is projected to last 5 years and consists of approximately 200 individual target stars. Among these, 25-50 planetary systems can be studied spectroscopically, which will include the search for gases such as CO(2), H(2)O, CH(4), and O(3). Many of the key technologies required for the construction of Darwin have already been demonstrated, and the remainder are estimated to be mature in the near future. Darwin is a mission that will ignite intense interest in both the research community and the wider public.

Upper airway findings in patients with nocturnal breathing disorders.

This prospective open study was performed to examine the relation between pathologic findings of the upper respiratory tract and the types of noncentral sleep disorders (rhonchopathy, obstructive sleep apnea). 312 men and 274 women aged between 35-75 years attended our outpatient department for relief of their nocturnal breathing disorder. About 1/3 of the patients suffered only of habitual rhonchopathy and 2/3 were obstructive. No findings of the head and neck examination could predict the degree of oxygen desaturation, although pathologies of the nose (73.68%), the soft palate (94.1%) and narrowing of the oro- and hypopharynx (74.19%) were very common in patients with sleep disorder. At least one pathology could be found in every patients. The more pathologies were found the higher was the risk of obstructive sleep apnoea with desaturation below 70%. Unrelated tonsillectomy (51.36%) did not prevent nocturnal breathing disorders.

A central venous catheter coated with benzalkonium chloride for the prevention of catheter-related microbial colonization.

In an attempt to overcome infections associated with central venous catheters, a new antiseptic central venous catheter coated with benzalkonium chloride on the internal and external surfaces has been developed and evaluated in a clinical trial. Patients (235) randomly received either a triple-lumen central venous catheter coated with benzalkonium chloride (117) or a polyurethane non-antiseptic catheter (118). The incidence of microbial colonization of both catheters and retained antiseptic activity of the benzalkonium chloride device following removal were determined. The benzalkonium chloride resulted in a significant reduction of the incidence of microbial colonization on both the internal and external catheter surfaces. The reduction in colonization was detected at both the intradermal (21 benzalkonium chloride catheters vs. 38 controls, P = 0.0016) and distal segments of the antiseptic-coated catheters. Following catheter removal retained activity was demonstrated in benzalkonium chloride catheters which had been in place for up to 12 days. No patients developed adverse reactions to the benzalkonium chloride catheters. The findings demonstrate that the benzalkonium chloride catheter significantly reduced the incidence of catheter-associated colonization.

Synergistic interactions between ampakines and antipsychotic drugs.

Tests were made for interactions between antipsychotic drugs and compounds that enhance synaptic currents mediated by alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid-type glutamate receptors ("ampakines"). Typical and atypical antipsychotic drugs decreased methamphetamine-induced hyperactivity in rats; the effects of near or even subthreshold doses of the antipsychotics were greatly enhanced by the ampakines. Interactions between the ampakine CX516 and low doses of different antipsychotics were generally additive and often synergistic. The ampakine did not exacerbate neuroleptic-induced catalepsy, indicating that the interaction between the different pharmacological classes was selective. These results suggest that positive modulators of cortical glutamatergic systems may be useful adjuncts in treating schizophrenia.

Evaluation of distal anastomotic intimal hyperplasia: an experimental comparison by arteriography, duplex sonography, angioscopy, and intravascular ultrasound.

Routine follow-up investigation methods after peripheral arterial bypass surgery, such as arteriography and colour duplex sonography, do not always allow correct analysis of moderate alterations in the vessel wall, e.g. initial stages of distal anastomotic intimal hyperplasia (DAIH). The aim of this study was to evaluate the efficiency of angioscopy and intravascular ultrasound compared to the named routine methods regarding detection of early DAIH. Eight months after bilateral femoropopliteal bypass surgery with venous grafts in 18 sheep, we investigated the distal anastomotic sites using the named methods. The findings were then correlated to histologic specimens. Intravascular ultrasound presented the highest sensitivity followed by angioscopy, with results markedly different from the findings arrived at by conventional methods.

The haemopoietic effects of thrombopoietin administered post-myelosuppressive carboplatin therapy compared to either pre- and post- or pre-chemotherapy.

Balb/c mice (n = 10) were treated with 50 microg/kg recombinant human thrombopoietin (rhTPO) or placebo control by subcutaneous injection daily for 5 d before (pre), or 8d after (post), or 5 d before and 8d after (pre/post) carboplatin (125 mg/kg). RhTPO given post significantly abrogated the platelet (PLT) nadir (413.0 +/- 52.0 v 42.0 +/- 6.0 (x10(9)/l), P<0.01), reduced days to mean PLT recovery (2 v 8d), and increased progenitor (CFU-Meg) colony formation (74.7 +/- 6.7 v 40.7 +/- 3.3 (colonies/10(5) cells), P<0.001) compared to controls. Further, rhTPO given pre/post also significantly abrogated the PLT nadir (132 +/- 29 v 42.0 +/- 6.0 (x10(9)/l), P<0.05), increased megakaryocytes per high-powered field (MHPF) (5.67 +/- 0.9 v 0.33 +/- 0.3, P<0.001) and CFU-Meg (137.7 +/- 13.9 v 40.7 +/- 3.3, P<0.001) compared with controls. However, when comparing the three treatment groups, animals receiving rhTPO post exhibited significantly higher PLT nadirs (413.0 +/- 52.0 v 190 +/- 29 and 132 +/- 29 (x 10(9)/l), P<0.01) and increased CFU-GM (93.7 +/- 10.7 v 20.33 +/- 0.9 and 14.7 +/- 1.45, P< 0.001). All rhTPO groups experienced an abrogation of the haematocrit (HCT) nadir (P< 0.01), although, only the post cohort had a reduction in the days to mean HCT recovery (2 v 12d, P<0.01). These results suggested that post therapeutic rhTPO (post) appears to be more effective in abrogating the platelet nadir and enhancing platelet and HCT recovery following myelosuppressive chemotherapy, than either prophylactic or pre- and post-rhTPO therapy.

Tissue response to biomaterials used for staple-line reinforcement in lung resection: a comparison between expanded polytetrafluoroethylene and bovine pericardium.

OBJECTIVE: A study in a canine model of lung-reduction surgery evaluated the tissue response to polytetrafluoroethylene (ePTFE) and bovine pericardium (BP) used for staple-line reinforcement. METHODS: In each of ten dogs, BP was placed in one lung and ePTFE in the other. The implants were retrieved at 30, 95, or 167 days after implantation and studied histologically. The connective tissue covering the implants was measured and analysis of variance was used to compare results with the two materials. RESULTS: At 30 days, the BP specimens showed focal chronic inflammation and thin tissue coverage, whereas the ePTFE specimens had no focal inflammation and thick tissue coverage. At 95 and 167 days, the inflammation in the BP specimens had resolved, but tissue coverage remained minimal, and there was no resorption of the BP. In the ePTFE specimens, tissue coverage had increased. Analysis of variance comparing representative tissue specimens showed that the tissue encapsulating the ePTFE was significantly thicker than that surrounding the BP (P < 0.0001). No air leaks, staple-line disruptions, or infections occurred in the study. CONCLUSIONS: Neither ePTFE nor BP is resorbable. Both materials have been used successfully, without resultant infections, for clinical staple-line reinforcement. The more favorable tissue response to ePTFE observed in this study may have clinical ramifications. Comparative clinical studies of the two materials are needed.

Potential for secondary poisoning and biomagnification in marine organisms.

For selected priority pollutants, like organochlorine pesticides, PAHs and PCBs, and mercury and cadmium, the transfer along marine food chains was assessed based on monitoring data. Comparison of the acquired body burden for marine fish and the toxicity thresholds for predating marine birds and mammals provides evidence for the relevance of contaminant uptake with the food and the liability for secondary poisoning. As a consequence, contaminant residues in prey organisms (critical body burden) should be used for marine hazard and risk assessments. Evaluations solely from aquatic exposure concentrations are not adequate to account for potential secondary effects in marine ecosystems.

Sequential treatment with rmIL-3 or simultaneous treatment with rmIL-3 or rhIL-11 with thrombopoietin (TPO) fails to enhance in vivo neonatal rat thrombocytopoiesis.

Multipotent-lineage nondominant growth factors, acting alone or in combination with lineage-dominant cytokines, are known to influence both myelopoiesis and thrombocytopoiesis. Interleukin (IL)-3 and IL-11 stimulate and expand multilineage progenitor cells and induce thrombocytopoiesis. These cytokines also act synergistically with various other lineage dominant and lineage-nondominant cytokines in vitro to expand primitive and committed hematopoietic stem cells. In this study we investigated the in vivo effects of IL-3 and IL-11 in combination with the c-mpl ligand, thrombopoietin (rhTPO), on neonatal rat hematopoiesis. Newborn Sprague-Dawley rats (24 36 hours old, weighing 6-8 g) were intraperitoneally injected with rhTPO (10 microg/kg) for 14 days, rmIL-3 (10 microg/kg) for 5 days followed by rhTPO (10 microg/kg) for 9 days, rmIL-3 (10 microg/kg) + rhTPO (10 microg/kg) for 14 days, rhIL-11 (250 microg/kg) + rhTPO (10 microg/kg) for 14 days, or PBS/human serum albumin (HSA) for 14 days. When compared with PBS/HSA, rhTPO at a dosage of 10 microg/kg significantly increased platelet count (10(-9) L) (day 6, 569 +/- 37.1 vs. 1446 +/- 43.8, p < 0.001; day 10, 796 +/- 68.3 vs. 1774 +/- 238.4, p < 0.01; day 14, 850 +/- 64.4 vs. 3441 +/- 98.1 /10(-9) l, p < 0.001) and absolute neutrophil count (ANC) (day 6, 335.2 +/- 59.6 vs. 752 +/- 335.2, p < 0.01; day 12, 664 +/- 54.1 vs. 1520 +/- 158.2, p < 0.01). However, rhTPO has no effect on the circulating hematocrit or red blood cell count. RhTPO-treated animals also displayed higher platelet counts (/10(-9) L) vs. rhIL-11 or rhIL-6 beginning on day 6 (day 6, 1597.6 +/- 134.7 vs. 930.7 +/- 67.3 vs. 863 +/- 19.6, p < 0.01; day 8, 1686 +/- 208.4 vs. 990 +/- 29.4, vs. 977 +/- 34.33, p < 0.05; day 10, 1774 +/- 238.4 vs. 1096 +/- 49.6, vs. 937 +/- 65, p < 0.01; day 14, 2187 +/- 127.5 vs. 1280 +/- 35.8 vs. 951 +/- 50.7 /10(-9) L, p < 0.01). Sequential administration of rmIL-3 followed by rhTPO resulted in no significant increase in platelet counts compared with PBS-HSA/rhTPO. RhTPO + rmIL-3 given simultaneously also had no additive effect on the circulating platelet count compared with rhTPO alone. Similarly, no additive effect on circulating platelet counts was observed with rhIL-11 + rhTPO vs. rhTPO alone. Bone marrow studies showed a significant increase in the number of megakaryocytes per high-power field in all the groups treated with rhTPO vs. control (p < 0.05), but no additive effect was seen in neonatal rats additionally receiving either rmIL-3 or rhIL-11. Colony forming unit (CFU)-Meg colony formation was also significantly increased in all the groups treated with rhTPO vs. control (p < 0.05), with no additive effect observed after the addition of either rmIL-3 or rhIL-11. These data suggest that rhTPO is more effective than rmIL-3 or rhIL-11 in inducing neonatal in vivo thrombocytopoiesis in rats, and that no additive effect is to be expected when rhTPO is combined sequentially with rhIL-3 or simultaneously with either rmIL-3 or rhIL-11. We hope that these preclinical data will provide insight into the design and future application of these thrombopoietic cytokines, alone or in combination, to prevent or treat thrombocytopenia.

Fistula formation after implanting an ePTFE membrane. A case report.

BACKGROUND: Expanded polytetrafluoroethylene (ePTFE) membranes have been used successfully as permanent implants to prevent adhesions after gynecologic surgery. Fistulization involving such an implant has not been reported previously. CASE: A 27-year-old woman had micturition problems and pain four years after a myomectomy and implantation of an ePTFE membrane. Laparotomy revealed that the membrane was partly inserted into a hole in the anterior bladder wall, close to the vesicouterine pouch. The membrane was removed and the fistula repaired. Pathologic studies of the specimen showed multispecies bacterial contamination. CONCLUSION: The fistula may have originated with ischemia at the vesicouterine fold caused by the suture in the corner of the ePTFE membrane. This led to intussusception of the prosthesis. The hole that was created expanded, and pelvic inflammatory disease probably produced the local sepsis. In patients with posterior or fundal uterine incisions for myomectomy, the ePTFE membrane is a useful permanent adhesion barrier in an area at substantial risk of adhesion formation. In cases using anterior incisions, however, in which the membrane may be fixed close to the vesicouterine fold, surgeons should consider removing the prosthesis after peritoneal healing has occurred.

A longitudinal assessment of hormonal and physical alterations during normal puberty in boys. II. Estrogen levels as determined by an ultrasensitive bioassay.

A limited number of reports of estrogen levels in prepubertal and early pubertal boys have been published because previous estrogen assays have lacked adequate sensitivity to quantitate circulating estrogen concentrations. Development of a new ultrasensitive assay has permitted measurement of estrogen levels in 23 normally growing boys progressing through puberty. Concentrations were measured at approximately 4-month intervals over a 5- to 8-yr period. The levels increased with maturation in all and correlated directly with chronological age, bone age, weight, height, pubertal stage, and testosterone and insulin-like growth factor-I levels. Of these factors, the level of testosterone had the greatest influence on the estrogen concentration. The time from peak growth velocity also significantly correlated with estrogen level. The estrogen level correlated positively with growth velocity before the time of peak growth velocity and negatively after peak growth velocity. The estrogen levels first increased significantly an average of 3 yr after pubertal onset and reached a peak by 5 yr after pubertal onset. Peak growth velocity was attained an average of 3 yr after pubertal onset. The greatest increase in the rate of rise of the estrogen level was an 11-fold rise during the year in which puberty began. The next most significant increase was a 4.8-fold rise 3 yr after pubertal onset. With respect to pubertal stage, the greatest absolute change occurred from stage 4 to stage 5 and the greatest fold change occurred from stage 1 to stage 2. The estrogen level did not significantly correlate with the 24-h GH level. In conclusion, circulating estrogen levels are very low in all boys prepubertally and rise steadily during adolescent development. The estrogen level is closely related to testosterone concentration and to the time of peak growth velocity. These findings are consistent with the hypothesis that estrogen at low levels augments skeletal growth and maturation in boys (as well as girls). They are also consistent with the hypothesis that continued exposure to estrogen leads to epiphyseal fusion. Further studies are required to define the separate and combined roles of estrogen, GH, and testosterone, as well as other factors, on growth and sexual development at puberty.

Time course for effects of hypoglycemia on insulin gene transcription in vivo.

The purpose of these studies was to determine the time course for onset of effects of hypoglycemia on insulin gene transcription in vivo. Using insulin infusions, we found that insulin-induced hypoglycemia decreased levels of precursors for insulin mRNA, reflecting changes in new mRNA synthesis, to new steady-state values within 100 min. These changes were followed by declines in processed insulin mRNA. An alternate infusion technique was developed to lower plasma glucose levels from a constant level of 120-130 to 50-60 mg/dl in < 10 min without changing insulin levels from those maintained during a preceding 1-h control period. Using this protocol, we found that levels of precursors for insulin mRNA remained constant for the first 20 min of hypoglycemia, then decreased rapidly at 40 and 60 min. The initial delay followed by rapid decline suggests that the decrease of insulin gene transcription in response to hypoglycemia is an active process requiring one or more inductive events before implementation.

Spatial Organization and Time Dependence of Jupiter's Tropospheric Temperatures, 1980-1993.

The spatial organization and time dependence of Jupiter's temperatures near 250-millibar pressure were measured through a jovian year by imaging thermal emission at 18 micrometers. The temperature field is influenced by seasonal radiative forcing, and its banded organization is closely correlated with the visible cloud field. Evidence was found for a quasi-periodic oscillation of temperatures in the Equatorial Zone, a correlation between tropospheric and stratospheric waves in the North Equatorial Belt, and slowly moving thermal features in the North and South Equatorial Belts. There appears to be no common relation between temporal changes of temperature and changes in the visual albedo of the various axisymmetric bands.

Perioperative myocardial ischemia. Its relation to anatomic pattern of coronary artery stenosis.

BACKGROUND: Recently, the frequency of intraoperative myocardial ischemic episodes in patients with steal-prone coronary anatomy, compared with other groups of patients undergoing coronary artery surgery (CABG), has been characterized. Because the relationship between anatomic distribution of coronary stenosis and myocardial ischemic episodes over the entire perioperative period has not been well defined, the authors sought to examine this relationship in 100 adult patients undergoing CABG surgery. METHODS: Continuous electrocardiographic (ECG) monitoring was performed in the pre-, intra-, and postoperative periods, quantifying the frequency (episodes/hour of monitoring [epis/h]) and duration (minutes/hour of monitoring [min/h]) of ECG ischemic episodes defined as a reversible ST segment shift > or = 1 mm at J + 60 ms of > or = 1 min duration. Based on preoperative coronary angiography, patients were categorized into the following groups: group 1 (n = 40), steal-prone coronary anatomy (occluded major coronary artery and > or = 50% stenosis of left main coronary artery or > or = 70% proximal stenosis 2 (n = 17), left main or equivalent coronary stenosis (> or = 50% stenosis of left main coronary artery or > or = 70% proximal stenosis of the left anterior descending and circumflex coronary arteries); and group 3 (n = 43), coronary artery stenosis > or = 70% not fitting the preceding categories. RESULTS: Compared with group 3, patients in group 1 had more frequent and longer ECG ischemic events preoperatively, and were nearly two times more likely (relative risk 1.82, 95% confidence interval 1.07-3.10) to develop an ischemic event during this period. There were no differences in the relative risk, frequency, or duration of an ischemic episode between groups 1 and 3 during the intraoperative and postoperative periods, or between groups 1 and 2 or groups 2 and 3 during any perioperative period. In group 2 patients, the frequency of ischemic epis/h was less intra- compared with preoperatively, while, in group 3, the ischemic epis/h decreased postoperatively compared with the intraoperative period. The duration of ischemic episodes (min/h) in group 3, however, increased postoperatively compared with the pre- and intraoperative periods, while, in group 2, the duration of ischemic episodes (min/h) was less intraoperatively compared with the preoperative period. Ninety-seven percent of preoperative ECG ischemic episodes occurred without symptoms. Postoperative myocardial infarction occurred in three patients in group 3, two in group 2, and one in group 1. There were no perioperative deaths. CONCLUSION: These data indicate that, compared with patients with non-left main or equivalent coronary stenosis, those with steal-prone coronary anatomy have more frequent and longer ECG ischemic episodes preoperatively. The data also indicate that there are no other differences in the risk, frequency, or duration of ischemic episodes between groups perioperatively. Thus, different distributions of coronary artery stenosis may be associated with changes in the perioperative characteristics of ECG ischemic episodes.

Diamonds in dense molecular clouds: a challenge to the standard interstellar medium paradigm.

Observations of a newly discovered infrared C-H stretching band indicate that interstellar diamond-like material appears to be characteristic of dense clouds. In sharp contrast, the spectral signature of dust in the diffuse interstellar medium is dominated by -CH2- and -CH3 groups. This dichotomy in the aliphatic organic component between the dense and diffuse media challenges standard assumptions about the processes occurring in, and interactions between, these two media. The ubiquity of this interstellar diamond-like material rules out models for meteoritic diamond formation in unusual circumstellar environments and implies that the formation of the diamond-like material is associated with common interstellar processes or stellar types.