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PubMed2003

Patent first, ask questions later: morality and biotechnology in patent law.

This Article explores the U.S. "patent first, ask questions later" approach to determining what subject matter should receive patent protection. Under this approach, the U.S. Patent and Trademark Office (USPTO or the Agency) issues patents on "anything under the sun made by man," and to the extent a patent's subject matter is sufficiently controversial, Congress acts retrospectively in assessing whether patents should issue on such interventions. This practice has important ramifications for morally controversial biotechnology patents specifically, and for American society generally. For many years a judicially created "moral utility" doctrine served as a type of gatekeeper of patent subject matter eligibility. The doctrine allowed both the USTPO and courts to deny patents on morally controversial subject matter under the fiction that such inventions were not "useful." The gate, however, is currently untended. A combination of the demise of the moral utility doctrine, along with expansive judicial interpretations of the scope of patent-eligible subject matter, has resulted in virtually no basis on which the USTPO or courts can deny patent protection to morally controversial, but otherwise patentable, subject matter. This is so despite position statements by the Agency to the contrary. Biotechnology is an area in which many morally controversial inventions are generated. Congress has been in react-mode following the issuance of a stream of morally controversial biotech patents, including patents on transgenic animals, surgical methods, and methods of cloning humans. With no statutory limits on patent eligibility, and with myriad concerns complicating congressional action following a patent's issuance, it is not Congress, the representative of the people, determining patent eligibility. Instead, it is patent applicants, scientific inventors, who are deciding matters of high public policy through the contents of the applications they file with the USTPO. This Article explores how the United States has come to be in this position, exposes latent problems with the "patent first" approach, and considers the benefits and disadvantages of the "ask questions first, patents later" approaches employed by some other countries. The Article concludes that granting patents on morally controversial biotech subject matter and then asking whether such inventions should be patentable is bad policy for the United States and its patent system, and posits workable, proactive ways for Congress to successfully guard the patent-eligibility gate.

Animals↗

PubMed2006

Management of pediatric radiation dose using GE fluoroscopic equipment.

In this article, we present GE Healthcare's design philosophy and implementation of X-ray imaging systems with dose management for pediatric patients, as embodied in its current radiography and fluoroscopy and interventional cardiovascular X-ray product offerings. First, we present a basic framework of image quality and dose in the context of a cost-benefit trade-off, with the development of the concept of imaging dose efficiency. A set of key metrics of image quality and dose efficiency is presented, including X-ray source efficiency, detector quantum efficiency (DQE), detector dynamic range, and temporal response, with an explanation of the clinical relevance of each. Second, we present design methods for automatically selecting optimal X-ray technique parameters (kVp, mA, pulse width, and spectral filtration) in real time for various clinical applications. These methods are based on an optimization scheme where patient skin dose is minimized for a target desired image contrast-to-noise ratio. Operator display of skin dose and Dose-Area Product (DAP) is covered, as well. Third, system controls and predefined protocols available to the operator are explained in the context of dose management and the need to meet varying clinical procedure imaging demands. For example, fluoroscopic dose rate is adjustable over a range of 20:1 to adapt to different procedure requirements. Fourth, we discuss the impact of image processing techniques upon dose minimization. In particular, two such techniques, dynamic range compression through adaptive multiband spectral filtering and fluoroscopic noise reduction, are explored in some detail. Fifth, we review a list of system dose-reduction features, including automatic spectral filtration, virtual collimation, variable-rate pulsed fluoroscopic, grid and no-grid techniques, and fluoroscopic loop replay with store. In addition, we describe a new feature that automatically minimizes the patient-to-detector distance, along with an estimate of its dose reduction potential. Finally, two recently developed imaging techniques and their potential effect on dose utilization are discussed. Specifically, we discuss the dose benefits of rotational angiography and low frame rate imaging with advanced image processing in lieu of higher-dose digital subtraction.

Body Burden↗

PubMed2002

Virtual reality-based post-stroke hand rehabilitation.

A VR-based system using a CyberGlove and a Rutgers Master II-ND haptic glove was used to rehabilitate four post-stroke patients in the chronic phase. Each patient had to perform a variety of VR exercises to reduce impairments in their finger range of motion, speed, fractionation and strength. Patients exercised for about two hours per day, five days a week for three weeks. Results showed that three of the patients had gains in thumb range (50-140%) and finger speed (10-15%) over the three weeks trial. All four patients had significant improvement in finger fractionation (40-118%). Gains in finger strength were modest, due in part to an unexpected hardware malfunction. Two of the patients were measured against one-month post intervention and showed good retention. Evaluation using the Jebsen Test of Hand Function showed a reduction of 23-28% in time completion for two of the patients (the ones with the higher degrees of impairment). A prehension task was performed 9-40% faster for three of the patients after the intervention illustrating transfer of their improvement to a functional task.

Aged↗

PubMed2006

Laparoscopic transcystic duct common bile duct exploration.

The modern era of common bile duct (CBD) surgery started with Mirizzi, who introduced intraoperative cholangiography in 1932. Intraoperative choledoscopy had been developed as an adjunctive to intraoperative cholangiography, which helped to detect CBD stones in an additional 10% to 15% of instances that otherwise would have been missed. Findings have shown choledochoscopy to be an important technique for efficient and effective management of CBD stones. Efforts to treat patients with common duct stones in one session and to avoid the potential complications of endoscopic sphincterotomy resulted in several laparoscopic transcystic CBD (LTCBDE) techniques. The techniques of transcystic stone extraction include lavage, trolling with wire baskets or biliary balloon catheters, cystic duct dilation, biliary endoscopy, and stone retrieval with wire baskets under direct vision and antegrade sphincterotomy, lithotripsy, and catheter techniques. The indications for LTCBDE are filling or equivocal defects at cholangiography, stones smaller than 10 mm, fewer than 9 stones, and possible tumor. The contraindications are stones larger than 1 cm, stones proximal to the cystic duct entrance into the CBD, small friable cystic duct, and 10 or more stones. Experience with LTCBDE shows that the approach is applicable in more than 85% of cases, with a success rate of 85% to 95%. It also is shown to be more cost effective than postoperative endoscopic retrograde cholangiopancreatography. Recent developments in LTCBDE have focused mainly on implementation of robotically assisted surgery and new imaging methods such as magnetic resonance cholangiopancreatography with three-dimensional virtual cholangioscopy and three-dimensional ultrasound. Further technological advances will facilitate the application of laparoscopic approaches to the common duct, which should become the primary strategy for the great majority of patients.

Ampulla of Vater↗

PubMed2001

Serine/threonine kinases as molecular targets of antidepressants: implications for pharmacological treatment and pathophysiology of affective disorders.

It is currently a widely accepted opinion that adaptive, plastic changes in the molecular and cellular components of neuronal signaling systems correlate with the effects on mood and cognition observed after long-term treatment with antidepressant drugs. Protein phosphorylation represents a key step for most signaling systems, and it is involved in the regulation of virtually all cellular functions. Two serine/threonine kinases, Ca2+ /calmodulin-dependent protein kinase II and cyclic AMP-dependent protein kinase, have been shown to be activated in the brain following antidepressant treatment. The changes in kinase activity are mirrored by changes in the phosphorylation of selected protein substrates in subcellular compartments (presynaptic terminals and microtubules), which, in turn, may contribute to the modulation of synaptic transmission observed with antidepressants. The molecular consequences of protein kinase activation may account for some of the alterations in neural function induced by antidepressants, and may suggest novel possible strategies of pharmacological intervention.

Animals↗

PubMed2005

Modern fat technology: what is the potential for heart health?

Saturated and trans-fatty acids raise total cholesterol and LDL-cholesterol and are known to increase the risk of CHD, while dietary unsaturated fatty acids play important roles in maintaining cardiovascular health. Replacing saturated fats with unsaturated fats in the diet often involves many complex dietary changes. Modifying the composition of foods high in saturated fat, particularly those foods that are consumed daily, can help individuals to meet the nutritional targets for reducing the risk of CHD. In the 1960s the Dutch medical community approached Unilever about the technical feasibility of producing margarine with a high-PUFA and low-saturated fatty acid composition. Margarine is an emulsion of water in liquid oil that is stabilised by a network of fat crystals. In-depth expertise of fat crystallisation processes allowed Unilever scientists to use a minimum of solid fat (saturated fatty acids) to structure a maximum level of PUFA-rich liquid oil, thus developing the first blood-cholesterol-lowering product, Becel. Over the years the composition of this spread has been modified to reflect new scientific findings and recommendations. The present paper will briefly review the developments in fat technology that have made these improvements possible. Unilever produces spreads that are low in total fat and saturated fat, virtually free of trans-fatty acids and with levels of n-3 and n-6 PUFA that are in line with the latest dietary recommendations for the prevention of CHD. Individuals with the metabolic syndrome have a 2-4-fold increased risk of developing CHD; therefore, these spreads could make a contribution to CHD prevention in this group. In addition, for individuals with the metabolic syndrome the spreads could be further modified to address their unique dyslipidaemia, i.e. elevated blood triacylglycerols and low HDL-cholesterol. Research conducted in the LIPGENE study and other dietary intervention studies will deliver the scientific evidence to justify further modifications in the composition of spreads that are healthy for the heart disease risk factors associated with the metabolic syndrome.

Cardiovascular Diseases↗

PubMed1985

Biochemical, metabolic, and clinical role of copper in human nutrition.

Veterinary nutritional science has embraced the study of copper for decades, but copper has languished as an orphan among human nutritionists because of the obscurity of clinical copper-deficiency states in man. As medical investigators, we may have gone down a long road, missing the forest for the trees. Indeed, overt copper-deficiency syndromes in humans have been recognized since the 1960s, and the list of contributing factors is expanding. Unwise self-medication with megadoses of zinc, for instance, might produce a mini-epidemic of copper deficiency. Moreover, induced copper deficiency may someday prove to be a legitimate therapeutic intervention in some disease states. But, the influence of subtle differences in dietary intakes of copper on human health may be much more important than frank copper depletion. Moreover, the recognition of disordered copper metabolism simulating a deficiency state--as occurs in Menkes' KHS and in variant Elhers-Danlos syndrome--has important implications. The full description of the relationship that thionein and other intracellular proteins might have in the etiology of these alterations has yet to be written. The elegance of the interplay of biochemical defects, physiological dysfunction, and clinical manifestations in copper metabolism is virtually unmatched in nutritional biology; yet, our present abilities to determine human copper status are limited. Now that it is clear that intracellular redistribution as well as total-body depletion can effect the disruption of copper-dependent functions, a concerted effort to improve status assessment through the use of functional indices should become a high priority. Finally, the pursuit of the bases of copper's involvement in host defenses, antiotoxidant protection and carbohydrate metabolism--functions in which clear links to established mammalian cuproenzyme are at present elusive--should provide exciting substrate for investigators for years to come.

Adult↗

PubMed2000

Enhancing the Induction Skill of Deaf and Hard-of-Hearing Children with Virtual Reality Technology.

Many researchers have found that for reasoning and reaching a reasoned conclusion, particularly when the process of induction is required, deaf and hard-of-hearing children have unusual difficulty. The purpose of this study was to investigate whether the practice of rotating virtual reality (VR) three-dimensional (3D) objects will have a positive effect on the ability of deaf and hard-of-hearing children to use inductive processes when dealing with shapes. Three groups were involved in the study: (1) experimental group, which included 21 deaf and hard-of-hearing children, who played a VR 3D game; (2) control group I, which included 23 deaf and hard-of-hearing children, who played a similar two-dimensional (2D) game (not VR game); and (3) control group II of 16 hearing children for whom no intervention was introduced. The results clearly indicate that practicing with VR 3D spatial rotations significantly improved inductive thinking used by the experimental group for shapes as compared with the first control group, who did not significantly improve their performance. Also, prior to the VR 3D experience, the deaf and hard-of-hearing children attained lower scores in inductive abilities than the children with normal hearing, (control group II). The results for the experimental group, after the VR 3D experience, improved to the extent that there was no noticeable difference between them and the children with normal hearing.

Journal Article↗

PubMed1998

Hypothermia extends the cardioprotection by ischaemic preconditioning to coronary artery occlusions of longer duration.

OBJECTIVE: To test the hypothesis that mild hypothermia potentiates the cardioprotection afforded by ischaemic preconditioning so that infarct size limitation can be obtained after coronary artery occlusion (CAO) durations which exceed the cardioprotective range (> 90 min) of either hypothermia or ischaemic preconditioning alone. METHODS: Four groups of anaesthetized rats were subjected to different durations of CAO: (i) normothermia (N, 36.5-37.5 degrees C, n = 29), (ii) normothermia + ischaemic preconditioning (N + IP, 15 min CAO followed by 10 min of reperfusion, n = 35), (iii) hypothermia (H, 30-31 degrees C, n = 31) and (iv) hypothermia + ischaemic preconditioning (H + IP, n = 24). Infarct size (IA/AR) was determined after 3 hours of reperfusion using trypan blue to delineate the area at risk (AR) from non-risk region and nitroblue tetrazolium to delineate infarcted area (IA) from viable myocardium. RESULTS: In N the CAO duration versus infarct size relation had a sigmoid shape with virtually no infarction occurring at 15 min CAO and 56 +/- 5% of the area at risk being infarcted at 30 min CAO reaching a plateau of 71 +/- 2% at 60 min CAO. Hypothermia produced a rightward shift of the relation resulting in an approximately 15 min delay in onset of infarction. Ischaemic preconditioning produced a similar reduction in infarct size (23 +/- 4%) at 30 min CAO compared to hypothermia (13 +/- 3%) but also limited infarct size at 45 min to 36 +/- 3% and at 60 min CAO to 50 +/- 3% suggesting a slowing of infarct progression. Neither intervention limited IA/AR produced by 120 min CAO. In H + IP, combined hypothermia and ischaemic preconditioning resulted in synergistic infarct size reduction so that at 45 min and 60 min CAO IA/AR was reduced to 17 +/- 3% and 23 +/- 3%, respectively, and even at 120 min CAO to 58 +/- 5%, which was significantly smaller than during normothermic control conditions (p < 0.05 vs. N). CONCLUSION: Mild hypothermia limited IA/AR modestly but markedly enhanced the cardioprotection afforded by ischaemic preconditioning in the in situ rat heart so that irreversible damage produced by even prolonged coronary artery occlusions was limited.

Analysis of Variance↗

PubMed1999

Theory, method, and power in drug and HIV-prevention research: a participant-observer's critique.

Why do most substance misuse and HIV-prevention researchers not practice what they preach concerning the complementarity of quantitative and qualitative methods? Why does most of the public health literature fail to address the important intellectual and political debates that substance misuse and HIV infection confronts? Why is the entire field so timid with respect to social science theory? Most drug researchers, and virtually all the anthropologists working on the subject, publicly acknowledge the need to combine quantitative and qualitative methodologies. Surprisingly, however, there are almost no successful examples of substance misuse and HIV prevention research projects that meld quantitative methods with participant-observation approaches organically. While this methodological schism also holds true for most of the social sciences more broadly, in few other fields besides that of substance misuse research is the complementarity of quantitative and qualitative methods more urgently and obviously necessary. On the one hand this methodological dialogue has practical utility for creating better public health interventions that might relieve human suffering; and on the other hand this applied dialogue has the potential for a critical, multidisciplinary, theoretical impact on academia.

Anthropology, Cultural↗

PubMed1999

A system for microscope-assisted guided interventions.

We present a system for surgical navigation using stereo overlays in the operating microscope aligned to the operative scene. This augmented reality system provides 3D information about nearby structures and offers a significant advancement over pointer-based guidance, which provides only the location of one point and requires the surgeon to look away from the operative scene. With a previous version of this system, we demonstrated feasibility, but it became clear that to achieve convincing guidance through the magnified microscope view, a very high alignment accuracy was required. We have made progress with several aspects of the system, including automated calibration, error simulation, bone-implanted fiducials and a dental attachment for tracking. We have performed experiments to establish the visual display parameters required to perceive overlaid structures beneath the operative surface. Easy perception of real and virtual structures with the correct transparency has been demonstrated in a laboratory and through the microscope. The result is a system with a predicted accuracy of 0.9 mm and phantom errors of 0.5 mm. In clinical practice errors are 0.5-1.5 mm, rising to 2-4 mm when brain deformation occurs.

Bone Cysts↗

PubMed2000

Using potentially life-shortening drugs in neonates and infants.

OBJECTIVE: To describe the frequency, background, and impact of decisions to give analgesic or other drugs that may, intentionally or unintentionally, shorten the life-span of severely ill neonates. SETTING: The Netherlands. DESIGN: Retrospective, cross-sectional study. PATIENTS: Questionnaires were mailed in The Netherlands to physicians reporting 338 consecutive deaths of infants under 1 yr of age from August through November 1995. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Questions were asked about medical end-of-life decisions preceding the death of the infant and about the decision-making process. Potentially life-shortening drugs, mostly opioids, were given in 37% of all deaths. The estimated effect in terms of the shortening of life was <1 wk in 72% of all patients in whom the administration of potentially life-shortening drugs had been the most important end-of-life decision. Most decisions to administer such drugs were discussed with parents and colleagues. The decisions were discussed regarding virtually all patients in whom the physician had intended to hasten death; doses of opioids tended to be larger in this group. CONCLUSIONS: The frequency with which drugs that may shorten life are administered before the death of severely ill infants confirms the important role of modern medicine in dying in neonatology. Most physicians caring for neonates feel that palliative medication may be warranted in dying infants, even if it shortens life. A distinction between intentionally ending life and providing adequate terminal care by alleviating pain or other symptoms, which is important in moral and judicial terms, is probably not easily made for some of these patients.

Attitude of Health Personnel↗

PubMed2004

Blunt abdominal trauma: clinical value of negative screening US scans.

PURPOSE: To assess clinical and surgical outcomes in patients with blunt abdominal trauma and negative screening ultrasonographic (US) scans. MATERIALS AND METHODS: From a database of 4,000 patients who underwent screening US for suspected blunt abdominal trauma at a level 1 trauma center, the authors retrospectively identified 3,679 patients with negative US findings. In these patients, outcome was determined by means of retrospective review of the trauma registry and all radiologic, surgical, and autopsy reports. In patients with false-negative findings at screening US, all imaging studies and medical charts were also reviewed. Proportions were statistically compared by means of the Pearson chi(2) and Fisher exact tests. Monte Carlo estimation was applied when expected frequencies were low. RESULTS: Among the 3,679 patients with negative findings at screening US, 99.9% (n = 3,641) had no injuries (true-negative findings). Differences in true-negative rates as a function of year (P >.5) or time of day (P >.3) were not significant. Among the 3,641 patients with true-negative findings, 93.6% (n = 3,407) required no additional tests and 6.4% (n = 234) underwent computed tomography or other tests. The percentage of patients who underwent additional tests was significantly higher in the 1st year of the study (19.2%) than in subsequent years (all comparisons, P <.001). Thirty-eight patients had false-negative US findings for abdominal injury. The injuries that were missed in 24 patients were nonsurgical (those that were treated successfully without intervention or were considered minor at autopsy) and those in 14 patients were surgical (required surgical intervention). Cumulatively, 65 injuries were missed. The six most common injuries included retroperitoneal hematoma (n = 13) and injuries in the spleen (n = 10), liver (n = 9), kidney (n = 8), adrenal gland (n = 8), and small bowel (n = 7). Twenty-five of the 38 patients had no or trace hemoperitoneum. Mean diagnostic delay until recognition of missed injury was 16.8 hours +/- 4.3 (standard error of the mean). The missed injury was identified within 12 hours in 19 of the 38 patients and within 24 hours in 34. CONCLUSION: The combination of negative US findings and negative clinical observation virtually excludes abdominal injury in patients who are admitted and observed for at least 12-24 hours.

Abdomen↗

PubMed2002

Vitamin A supplements ameliorate the adverse effect of HIV-1, malaria, and diarrheal infections on child growth.

OBJECTIVE: Evidence from animal experiments and observational studies in humans suggests that vitamin A plays a fundamental role in physical growth. However, results from vitamin A supplementation trials in children are inconsistent; whereas some did not find an overall effect on growth, others found benefits only among specific groups, including children with low concentrations of serum retinol or short duration of breastfeeding. The apparent lack of an overall effect of vitamin A on growth could be attributed to context-specific distribution of conditions that affect both growth and the response to supplementation, eg, baseline vitamin A status, deficiency of other nutrients (fat, zinc), and the presence of infectious diseases. Human immunodeficiency virus (HIV) infection, malaria, and diarrheal disease adversely affect growth and are associated with increased prevalence of vitamin A deficiency. We hypothesize that vitamin A supplementation could ameliorate the adverse effect of these infections on child growth. METHODS: We conducted a randomized, clinical trial among 687 Tanzanian children who were 6 to 60 months of age and admitted to the hospital with pneumonia. Children were assigned to oral doses of 200 000 IU vitamin A (half that dose if <12 months) or placebo on the day of admission, a second dose on the following day, and third and fourth doses at 4 and 8 months after discharge from the hospital, respectively. Anthropometric measurements were obtained at baseline and at monthly visits to the study clinics during 12 months after the initial hospitalization. Surveillance on the incidence and severity of diarrhea and respiratory infections was conducted during biweekly visits, alternately at a study clinic and the child's home, using a pictorial diary that the mothers were trained to use. A blood specimen was drawn at baseline for determination of HIV status, malaria infection, and hemoglobin levels. We used mixed effects models to compare estimated total weight and height increases after 1 year of follow-up between treatment arms, overall and within levels of HIV status, malaria, and other possible baseline effect modifiers. We also assessed the potential modulating effect of vitamin A on the risk of stunting (height-for-age <-2 standard deviations of the gender-specific National Center for Health Statistics median reference) attributable to diarrheal and respiratory infections during follow-up, in the subset of children who were not stunted at baseline. A similar approach was followed for wasting (weight-for-height <-2 standard deviations of the reference median). Cox regression models were used to estimate relative risks and 95% confidence intervals (CI), treating episodes of infection as time-dependent covariates. RESULTS: A total of 554 children had at least 2 follow-up measurements of height or weight and constituted the study base. Baseline characteristics did not differ significantly by treatment arm. Seventy-three percent of the children were <2 years of age, and 37% were <12 months; 31% were stunted at baseline and 9% were wasted. Malaria (Plasmodium falciparum) and HIV infection were found in 24% and 9% of the children, respectively. Median duration of follow-up was 351 days, with 10 measurements/child, on average, irrespectively of treatment assignment. Supplementation with vitamin A among children who had HIV infection and were <18 months of age resulted in a significant length increase. Four months after the first dose, infants who were HIV positive in the vitamin A arm had gained, on average, 2.8 cm (95% CI: 1.0-4.6) more than children who received placebo, whereas no effect was observed among infants who were HIV negative (difference at 4 months: -0.2 cm; 95% CI: -0.8-0.5). Children who were <12 months of age and had malaria at enrollment experienced a 747-g (95% CI: 71-1423) higher yearly weight gain attributable to vitamin A; among children without malaria, however, the supplements did not have a significant effect (-57 g; 95% CI: -461-348). These results remained unchanged after controlling for indicators of the socioeconomic and nutritional status at baseline. Linear growth was also improved by vitamin A among children from households with poor water supply (0.8 cm/year; 95% CI: 0-1.5) but not in children with tap water in the house or compound (-1.0 cm/year; 95% CI: -1.9-0). Weight gain was greater among children with mid-upper arm circumference below the 25th percentile of the age-specific distribution at baseline (458 g/year; 95% CI: 1-905), but no benefit was evident among children with higher mid-upper arm circumference. The risk of stunting associated with episodes of persistent diarrhea (lasting 14 or more days) during follow-up was virtually eliminated by vitamin A supplements. Among children in the placebo group, the average risk of stunting associated with 1 or more episodes of persistent diarrhea between 2 consecutive visits was 5.2 times higher (95% CI: 2.4-11.2) than that of children without diarrhea or with acute episodes. In contrast, among children who received vitamin A, there was virtually no risk of stunting associated with persistent diarrhea (relative risk: 1.0; 95% CI: 0.3-1.3). This effect was slightly attenuated after controlling for the number of household possessions, gender, baseline low arm circumference, HIV infection, and presence of malaria parasites in blood. Vitamin A supplements did not modify the associations between respiratory infections and the risk of stunting or wasting. CONCLUSIONS: Vitamin A supplementation improves linear and ponderal growth in infants who are infected with HIV and malaria, respectively, and decreases the risk of stunting associated with persistent diarrhea. Supplementation could constitute a low-cost, effective intervention to decrease the burden of growth retardation in settings where infectious diseases are highly prevalent.

Acquired Immunodeficiency Syndrome↗

PubMed1995

[Video controlled, minimally invasive exposure of the abdominal aorta by retroperitoneal approach for aorto-iliac reconstructions].

The morbidity and mortality rate of aortoiliac reconstruction is significant even in patients who are at low risk undergoing aortic surgery. Beyond the general extent of vascular disease, the great surgical intervention using a large vertical midline or transverse abdominal incision is also responsible for this events. To decrease the surgical stress a new minimal retroperitoneal approach was developed. To exposure the infrarenal aortic segment a 7 cm left paramedian incision is used, a special retractor and modified surgical instruments combining direct visualization of the operation field with flexible videoendoscopic control. This new approach offers the possibility to decrease the operative stress and enables complete control if serious bleeding might occur. This 'minimally invasive' approach appears to diminish the catabolic response and is hopefully associated with accelerated recovery and virtual abolition of large wound-related complications.

Aorta, Abdominal↗

PubMed1995

Birth weight and perinatal mortality. A comparison of the United States and Norway.

OBJECTIVE: To compare perinatal mortality in the United States and Norway, using a new analytic approach based on relative birth weight. DESIGN: Comparison of linked birth and perinatal death records for US and Norwegian births from 1986 through 1987, the most recently available 2-year period. SETTING: Norway and the United States. PARTICIPANTS: A total of 7,445,914 US births and 105,084 Norwegian births. INTERVENTIONS: None. MAIN OUTCOME MEASURE: Perinatal weight-specific mortality after adjustment for each country's own mean birth weight. RESULTS: The higher rate of perinatal death in the United States compared with Norway is due to an excess of preterm deliveries in the United States. Low-weight, preterm births comprise 2.9% of US births compared with 2.1% of Norwegian births. If the United States could eliminate this slight excess of preterm delivery, perinatal mortality in the United States would decrease to the level in Norway. Unexpectedly, the survival of newborns at any given birth weight is virtually the same in the United States and Norway when newborns' birth weights are considered relative to their own nation's mean weight. CONCLUSIONS: Low rates of perinatal mortality in the Scandinavian countries have usually been attributed to the heavier weights of their newborns. Higher mortality among US infants is in fact due entirely to a small excess of preterm deliveries. The lighter weights of US newborns at term appear not to affect perinatal survival. Furthermore, the apparent survival advantage of low-weight US newborns (used by policymakers as evidence of superior US intensive neonatal care) may be at least partly an artifact. When weight-specific mortality rates are adjusted to relative birth weight, low-weight newborns have the same survival in Norway as in the United States. The prevention of excess mortality among US infants depends on the prevention of preterm births, not on changes in mean birth weight.

Birth Weight↗

PubMed2005

Comparison of pharmacological treatments for opioid-dependent adolescents: a randomized controlled trial.

CONTEXT: The prevalence of heroin and other opioid use has markedly increased among adolescents in the last decade; however, virtually no research has been conducted to identify effective treatments for this population. OBJECTIVE: To evaluate the relative efficacy of 2 pharmacotherapies, the partial opioid agonist buprenorphine hydrochloride and the centrally active alpha(2)-adrenergic blocker clonidine hydrochloride, in the detoxification of opioid-dependent adolescents. DESIGN, SETTING, AND PATIENTS: A double-blind, double-dummy, parallel-groups randomized controlled trial conducted in a university-based research clinic from October 2001 to December 2003. Patients were a volunteer sample of 36 adolescents who met DSM-IV criteria for opioid dependence (ages 13-18 years eligible). INTERVENTIONS: Participants were randomly assigned to a 28-day, outpatient, medication-assisted withdrawal treatment with either buprenorphine or clonidine. Both medications were provided along with thrice weekly behavioral counseling and incentives contingent on opiate abstinence. Postdetoxification, all participants were offered the opportunity for continued treatment with the opiate antagonist, naltrexone hydrochloride. MAIN OUTCOME MEASURES: Treatment retention, opiate abstinence, and human immunodeficiency virus risk behavior, along with measures of withdrawal and medication effects. RESULTS: A significantly greater percentage of adolescents who received buprenorphine were retained in treatment (72%) relative to those who received clonidine (39%) (P<.05). For those in the buprenorphine group, a significantly higher percentage of scheduled urine test results were opiate negative (64% vs 32%; P = .01). Participants in both groups reported relief of withdrawal symptoms and drug-related human immunodeficiency virus risk behavior. Those in the buprenorphine condition generally reported more positive effects of the medication. No evidence of opioid intoxication or psychomotor impairment was observed. Sixty-one percent of participants in the buprenorphine condition and 5% of those in the clonidine group initiated treatment with naltrexone. CONCLUSION: Combining buprenorphine with behavioral interventions is significantly more efficacious in the treatment of opioid-dependent adolescents relative to combining clonidine and behavioral interventions.

Administration, Cutaneous↗

PubMed1994

Characterization of atherosclerosis in a patient with familial high-density lipoprotein deficiency.

We describe the cardiovascular state of a 60-year-old homozygous patient with familial HDL deficiency (Tangier disease). The patient was examined by coronary angiography and intravascular ultrasound because of chest pain at rest and on exertion. We found a normal left ventricular function, moderately diffuse coronary sclerosis without stenosis and no critical stenosis of peripheral arteries. Intravascular ultrasound revealed the three layer appearance of arterial intima, media and adventitia with normal thickness. No calcified plaques or intimal hyperplasia could be detected apart from a single, discrete atherosclerotic lesion in one iliac artery segment. Concentric non-occlusive atherosclerotic lesions which are readily detectable with intravascular ultrasound were not found. The lack of severe atherosclerosis was remarkable insofar as massive foam cell formation and the virtually complete absence of circulating HDL is characteristic of Tangier disease and has been previously demonstrated in this patient. Our findings suggest that HDL deficiency and foam cell formation in Tangier disease are not necessarily associated with accelerated development of atherosclerosis.

Adult↗