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Background: Inhalational anesthetics can cause profound hemodynamic effects including decreases in systemic vascular resistance and cardiac inotropy. Although widely used in uncontrolled hemorrhagic shock (UHS), their consequences compared with other anesthetic regimens are not well-studied. Ketamine-based total intravenous anesthesia (TIVA) may produce less profound cardiovascular depression, and has been used during elective surgery but rarely during traumatic shock. The purpose of this study was to compare the effects of isoflurane (ISO) and TIVA regimens in a swine grade V liver injury model. We hypothesized that TIVA would result in less hypotension and dysfunctional inflammation than ISO. Methods: Twenty swine were randomized blindly to receive either 1% to 3% ISO, or intravenous ketamine, midazolam, and buprenorphine for maintenance anesthesia. Six animals acted as controls. After sedation and intubation, randomized anesthesia was initiated and monitored by an independent animal technician. Invasive lines were placed followed by celiotomy and splenectomy. Baseline mean arterial pressure (MAP) was documented and a grade V liver injury created. After 30 minutes of UHS, animals were resuscitated with 8 mL of Ringer's lactate per milliliter blood loss at 165 mL/ min. MAP and tissue oxygen saturation (StO 2 ) were continuously recorded. The animals were sacrificed 120 minutes after injury and lung tissue was harvested. Serum cytokines (interleukin-6 [IL-6], IL-8, and tumor necrosis factor-a [TNF-a]) were quantified with enzyme-linked immunosorbent assay. Lung cytokine mRNA levels were quantified with real time reverse transcriptase polymerase chain reaction. Results: Animal weight, liver injury pattern, and blood loss were similar (p > 0.1). The ISO group had a lower MAP at baseline (p = 0.02), at injury (p = 0.004), and study completion (p = 0.001). After resuscitation, MAP decreased in the ISO group but remained stable in the TIVA group. StO 2 was significantly higher in the TIVA group immediately after injury (p = 0.004), but similar between groups throughout the remainder of the study. Animals who received TIVA trended toward higher levels of lactate and lower pH throughout the study, reaching significance at 30 minutes postinjury (p = 0.037 and 0.043). Inflammatory cytokine (IL-6, IL-8, and TNF-a) production did not differ between groups, however TNF-a mRNA production was significantly lower in the TIVA group (p = 0.04). Conclusion: Although a TIVA regimen produced less pronounced hypotension in a swine model of UHS than did ISO, end-organ perfusion with TIVA appeared to be equivalent or inferior to ISO. In circumstances of limited resources, such as those experienced by forward Army surgical teams, a ketamine-based TIVA regimen may be an option for use in UHS.

Large bowel obstruction is a common problem with many different causes, the most common being colorectal adenocarcinoma, extracolonic adenocarcinoma, diverticular disease, volvulus, and inflammatory bowel disease. The nature of the obstruction can influence the best management. Historically, treatment of obstruction consisted of surgical removal of the obstruction if possible and decompression of the bowel with an ostomy. Other strategies for managing obstruction have evolved as alternatives to stomas, including primary resection with anastomosis and endoscopic stent placement. The choice of treatment can therefore be tailored to the individual patient with good success.

Editors' Note: Dr. Miyaji et al. and authors Sawai et al. debate moesin as a target molecule for CMV-related Guillain-Barre syndrome. Dr. Miyaji et al. were unable to validate the initial study, not identifying moesin antibodies in any of 41 patients with acute inflammatory demyelinating polyneuropathy (AIDP) using ELISA. The authors point out that the methodology differed from their study. Both groups agree that an animal model of AIDP through active immunization with moesin protein or passive transfer of immunoglobulin G antibodies is needed to confirm disease pathogenesis. —Megan Alcauskas, MD, and Robert C. Griggs, MD Sawai et al.1 reported moesin as a possible target molecule for cytomegalovirus (CMV)-related Guillain-Barre syndrome, especially acute inflammatory demyelinating polyneuropathy (AIDP). We aimed to validate their observations in our cohort of patients with AIDP by ELISA, which …

In a total-body irradiation (TBI), an absorbed dose of around 10 Gy is given to a patient with leukaemia within a couple of days. Delivery of a homogeneous dose throughout the whole body is difficult, and usually requires sophisticated irradation techniques. It is important to evaluate patient doses experimentally both for physical treatment planning and radiological protection. Organ and surface doses of patients were evaluated for a newly employed TBI technique - modified tracking technique. An experiment with a RANDO phantom demonstrated a good dose distribution over the whole body. Measurement of patient doses, however, revealed a variation of the doses between patients. Reproducibility of patient set-up is considered to be a critical factor for the variation, and improvement is desirable in this regard.

The sample and return mission to near Earth asteroid Nereus (4660) via an electric propulsion is presented in this paper, which is investigated at the Institute of Space and Astronautical Science (ISAS). An ion thruster is assumed here for Solar Electric Propulsion (SEP), which enables even the smallest spacecraft that weighs about only 350 kg to accomplish that difficult mission. ISAS is scheduling to launch one Lunar and one Martian orbiter in 1997 and 1998 via its own transporter M-V. And this concept follows them next in the launch window of 2002. The approach and exploration scenario to Nereus are also described here in detail, among which the mapping as well as sampling sequences are focused on. Especially, the sampling scheme proposed here is the characteristic point featuring an ‘artificial landmark’, which is the target plate dropped on the surface. This is used for the spacecraft to make a rendezvous autonomously with it via an optical aid onboard. Samples are assumed to be recovered via a hyperbolic reentry capsule on the ground. Practical weight estimation based on some heritages of ISAS does firm the spacecraft design feasibility.

This paper overviews recent attempts at co-integrating nano-electro-mechanical systems (NEMS) with nanoelectronic devices aiming to add more functionalities to conventional Si devices in ‘More-than-Moore’ domain and also explore novel physical principles in ‘Beyond CMOS’ domain.

Recent clinical studies have shown a sex dimorphism of morbidity and mortality due to shock, trauma, and sepsis, with females tolerating these insults better than males. Experimental animal studies have suggested that sex hormones have a pivotal role in this dimorphism. In the present investigation, a prospective cohort study at a university level-1 trauma center was conducted to evaluate the association between sex hormones and alterations in coagulation and inflammation. Patients with an admission to the intensive care unit, injury severity score (ISS) greater than 4, and obtainable consent were included in the study. In addition to routine clinical laboratories and patient outcomes, plasma TNF-[alpha], IL-6, IL-8, estradiol, progesterone, and testosterone were measured. Sixty-two patients (71% men, 29% women) met criteria for entry. Mean age was 42 +/- 17 years, and mean ISS was 23 +/- 13, with no statistical difference in age or ISS between sexes. Estradiol levels were positively correlated with ISS (P < 0.05) and negatively correlated with TNF-[alpha] (P < 0.01). Initial estradiol levels were higher in patients who developed an infection (P < 0.05). Testosterone was negatively correlated with age (P < 0.01) and was higher in patients who developed acute respiratory distress syndrome (P < 0.05) and in patients who did not survive (P < 0.05). The estradiol-to-progesterone ratio (E2-Pr) was higher in the survivors (P < 0.05). The E2-Pr had positive correlations with fibrinogen levels, rate of fibrin deposition and cross-linking, and overall clot strength (P < 0.05). Estradiol-to-progesterone ratio was negatively correlated with partial thromboplastin times (P < 0.01). In men, the E2-Pr was also negatively correlated with the time to onset of clot formation (P = 0.03). Sex hormone levels (or their ratios) were not correlated to platelet count or international normalized ratios. These findings provide evidence that sex hormone levels in the early posttraumatic period are significantly associated with alterations in the hemostatic and inflammatory response to trauma.

Joyo, the 100 MW t experimental reactor, has been successfully operated since 1977, and Monju, the 280 MW e prototype FBR, is under construction, with the first criticality planned for 1992. To promote FBR R&D efficiently — including the demonstration FBR (DFBR) programme — a steering committee for R&D was organized in 1986 by the Japan Atomic Power Company, the Power Reactor and Nuclear Fuel Development Corporation, the Japan Atomic Energy Research Institute and the Central Research Institute of Electric Power Industry. A design study of the DFBR is now underway to define its basic specifications by 1990. R&D for Monju, DFBR and future commercial FBRS has been done (1) to improve key technologies developed through the Joyo and Monju programmes; (2) to develop innovative technologies to make FBRS commercial; (3) to promote FBR development in conjunction with the development of the FBR fuel cycle.

In this paper, a surface recovery method using multiresolution wavelet transform is proposed. For representing 3-D surface shapes, 4th order B-spline functions are introduced as scaling functions of spline wavelets. A regularization problem is solved in order to estimate the surface function. The estimated surface function can be decomposed into an approximate surface function at specific lower resolution and the corresponding wavelet components by using the multiresolution wavelet transform. Consequently, by reducing the noise components which the wavelet components include, the surface recovery method can give a further accurate estimation of the surface function. Through several experiments, both the robustness to noises and the edge-preserving property in recovering the surface have been attained.

Pulmonary oedema and impairment of oxygenation are reported as common consequences of haemorrhagic shock and resuscitation (HSR). Surprisingly, there is little information in the literature examining differences in crystalloid type during the early phase of HSR regarding the development of pulmonary oedema, the impact on oxygenation and the haemodynamic response. These experiments were designed to determine if differences exist because of crystalloid fluid type in the development of oedema, the impact on oxygenation and the haemodynamic response to fluid administration in early HSR.Twenty anaesthetised swine underwent a grade V liver injury and bled without resuscitation for 30 minutes. The animals were randomised to receive, in a blinded fashion, either normal saline (NS; n = 10) or lactated Ringer's solution (LR; n = 10). They were then resuscitated with study fluid to, and maintained at, the preinjury mean arterial pressure (MAP) for 90 minutes.Extravascular lung water index (EVLWI) began to increase immediately with resuscitation with both fluid types, increasing earlier and to a greater degree with NS. A 1 ml/kg increase in EVLWI from baseline occurred after administartion of (mean +/- standard error of the mean) 68.6 +/- 5.2 ml/kg of normal saline and 81.3 +/- 8.7 ml/kg of LR (P = 0.027). After 150 ml/kg of fluid, EVLWI increased from 9.5 +/- 0.3 ml/kg to 11.4 +/- 0.3 ml/kg NS and from 9.3 +/- 0.2 ml/kg to 10.8 +/- 0.3 ml/kg LR (P = 0.035). Despite this, oxygenation was not significantly impacted (Delta partial pressure of arterial oxygen (PaO2)/fraction of inspired oxygen (FiO2)or= 100) until approximately 250 ml/kg of either fluid had been administered. Animals resuscitated with NS were more acidaemic (with lower lactates), pH 7.17 +/- 0.03 NS vs. 7.41 +/- 0.02 LR (P0.001).This study suggests that early resuscitation of haemorrhagic shock with NS or LR has little impact on oxygenation when resuscitation volume is less than 250 ml/kg. LR has more favourable effects than NS on EVLWI, pH and blood pressure but not on oxygenation.