In a consecutive series of 1109 patients undergoing aortic valve replacement (AVR) between January 1988 and December 1990, there were 48 patients (33 female, 15 male) over 80 years of age (mean age ...83.5 years, median 82.9 years). Of those, 33 had aortic stenosis and 15 combined aortic valve disease, with additional coronary artery disease being present in 36. Isolated AVR was performed in 25 patients, and it was combined with coronary venous bypass grafting, with 1-4 (mean 1.8) peripheral anastomoses in 23. Two patients died within 30 days (early mortality 4.2%). Non-fatal complications included one hemiparesis, four transient cerebral disorders, two cases of pneumonia which led to ventilatory assistance, three rethoracotomies because of postoperative bleeding, 15 tachycardias and one transient AV block. Late results were obtained after a median follow up time of 22 months. There were eight late deaths (four cardiac related, four not related) and a low incidence of non-fatal complications (two episodes of gastrointestinal bleeding while on oral anticoagulation, one cerebral transient ischemic attack and one acute left ventricular failure). Nine patients are in NYHA Class I, 12 in Class I-II, 11 in Class II, three in Class II-III and three in Class III. Of the surviving 38 patients, four are currently living in a home for the aged or a nursing home, while all the others are living in their own homes and are able to sustain a relatively independent life-style. We conclude that in very old patients with aortic valve disease, AVR can be performed with low mortality and few non-fatal complications.
Moisture sorption properties of gelatin powder and collagen fibers were investigated on the basis of the moisture sorption isotherm, the differential heat of moisture sorption, the decrease in ...entropy of moisture sorption and the parameter constants of the applicable isotherm equation. The amount of moisture sorbed on collagen fibers was larger than that on gelatin powder. The water molecules were absorbed on gelatin itself rather than on the active sites of gelatin. They were adsorbed on the polar groups of constitutive amino acids at amounts of moisture sorbed up to one or two monolayers and then were absorbed into collagen fibers at higher monolayers. They were kept loosely in gelatin and tightly in collagen. The structural stability of collagen to moisture was higher than that of gelatin.
To evaluate prospectively the incidence and severity of postoperative sore throat in 63 orotracheally intubated patients undergoing general anesthesia for various surgical procedures and to determine ...whether postoperative sore throat could be attenuated by treatment with the transdermal nonsteroidal anti-inflammatory drug ketoprofen applied on the anterior skin of the neck during operation.
Patients were randomly assigned to have treatment with ketoprofen (ketoprofen group) or to have placebo tape treatment (control group). Postoperative analgesia was obtained by continuous epidural infusion of local anesthetics, and no narcotics were administered intraoperatively or postoperatively. All patients were interviewed postoperatively after 12-20 hr using a scoring scale questionnaire. Sore throat was scored as 0=no sore throat, 1=minimal, 2=mild, 3=moderate, 4=severe.
In the control group, 16 of 32 patients had a sore throat. In the ketoprofen group, less patients (ten of 31 patients) had a sore throat (not significant). The severity of sore throat was alleviated significantly in the ketoprofen group (P <0.05).
This study suggests the pain caused by tracheal intubation is relieved by intraoperative topical use of transdermal ketoprofen.
We have reported that human chymase specifically cleaves big endothelins (ETs) at the Try31–Gly32bond, and produces novel trachea-constricting 31-amino-acid-length ETs, ETs(1-31). In this study, we ...investigated the effect of synthetic ETs(1-31) on the contractile activity toward porcine coronary arteries and rat aortae. Although ETs(1-31) exhibited less potent vasoconstrictile activity in these tissues than 21-amino-acid-length ETs(1-21), or a similar extent, ET-1(1-31) caused significantly slower-developing and longer-lasting contraction than ETs(1-21). The ETAreceptor antagonist, BQ485, completely inhibited the activity of ET-1(1-31). The ETBreceptor antagonist, BQ788, also inhibited the activity of ET-1(1-31) toward rat aortae more efficiently than that ET-1(1-21). Therefore, trachea-constricting peptides ETs(1-31) play roles as vasoconstrictors in a different manner from ETs(1-21).
Since we started using ventricular assist devices (VAD) in July 1987 up to August 1993, 63 of 15,650 (0.4%) patients (pts) who underwent open heart surgery were supported postoperatively by VAD at ...out institution. Forty-three were male and 20 female, mean age 55.5 years. In 49 pts coronary artery bypass grafting (CABG), in 8 pts valve surgery, in 3 pts combined CABG and valve surgery and in 3 pts corrective procedures for congenital heart disease were performed. Perioperative myocardial infarction was the most frequent indication (73%). In 37 of the 63 pts (58.7%) a centrifugal (Biomedicus pump (group A) was used and in 26 pts (41.3%) a pulsatile Abiomed BVS 5000 (group B). Fourteen of 37 pts (38%) in group A were weaned from the VAD and all of them were discharged. Twenty-three pts were unable to be weaned and 19 of these pts died. The remaining 4 pts were transplanted successfully and subsequently 3 died and 1 was discharged. In all, 15 pts (39%) were long-term survivors. Sixteen of 26 pts (62%) in group B were weaned from VAD and 13 (50%) of them were discharged of whom 3 died. Ten patients were unable to be weaned and 7 of these died. The remaining 3 pts were transplanted successfully. In all, 16 pts (61.5%) were long-term survivors. The shorter the interval between beginning resuscitation and application of VAD the better the outcome. Younger age, VAD installation in OR, support time between 2 and 7 days and Abiomed pump, influence the survival rate positively.
Secure Context-Sensitive Authorization Minami, K.; Kotz, D.
Third IEEE International Conference on Pervasive Computing and Communications,
2005
Conference Proceeding
There is a recent trend toward rule-based authorization systems to achieve flexible security policies. Also, new sensing technologies in pervasive computing make it possible to define ...context-sensitive rules, such as "allow database access only to staff who are currently located in the main office." However, these rules, or the facts that are needed to verify authority, often involve sensitive context information. This paper presents a secure context-sensitive authorization system that protects confidential information in facts or rules. Furthermore, our system allows multiple hosts in a distributed environment to perform the evaluation of an authorization query in a collaborative way; we do not need a universally trusted central host that maintains all the context information. The core of our approach is to decompose a proof for making an authorization decision into a set of subproofs produced on multiple different hosts, while preserving the integrity and confidentiality policies of the mutually untrusted principals operating these hosts
The human induced input of reactive N into the global biosphere has increased to approximately 150 Tg N each year and is expected to continue to increase for the foreseeable future. The need to feed ...(∼125 Tg N) and to provide energy (∼25 Tg N) for the growing world population drives this trend. This increase in reactive N comes at, in some instances, significant costs to society through increased emissions of NOx, NH3, N2O and NO3- and deposition of NOy and NHx. In the atmosphere, increases in tropospheric ozone and acid deposition (NOy and NHx) have led to acidification of aquatic and soil systems and to reductions in forest and crop system production. Changes in aquatic systems as a result of nitrate leaching have led to decreased drinking water quality, eutrophication, hypoxia and decreases in aquatic plant diversity, for example. On the other hand, increased deposition of biologically available N may have increased forest biomass production and may have contributed to increased storage of atmospheric CO2 in plant and soils. Most importantly, synthetic production of fertilizer N has contributed greatly to the remarkable increase in food production that has taken place during the past 50 years. The development of policy to control unwanted reactive N release is difficult because much of the reactive N release is related to food and energy production and reactive N species can be transported great distances in the atmosphere and in aquatic systems. There are many possibilities for limiting reactive N emissions from fuel combustion, and in fact, great strides have been made during the past decades. Reducing the introduction of new reactive N and in curtailing the movement of this N in food production is even more difficult. The particular problem comes from the fact that most of the N that is introduced into the global food production system is not converted into usable product, but rather reenters the biosphere as a surplus. Global policy on N in agriculture is difficult because many countries need to increase food production to raise nutritional levels or to keep up with population growth, which may require increased use of N fertilizers. Although N cycling occurs at regional and global scales, policies are implemented and enforced at the national or provincial/state levels. Multinational efforts to control N loss to the environment are surely needed, but these efforts will require commitments from individual countries and the policy-makers within those countries.
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