Rapid infusion system for neurosurgical treatment of massive intraoperative hemorrhage

Using an illustrative case of severe closed head injury that resulted in a posterior fossa epidural hematoma (EDH) and supratentorial epidural/subdural hematomas (SDH), the massive blood losses associated with operative repair of the torn sigmoid sinus and the significant fluid losses associated with refractory diabetes insipidus were treated by the intraoperative use of the Rapid Infusion System (RIS, Haemonetics). The RIS can rapidly infuse warm blood, crystalloid, or colloid at rates up to 1.5 L/min, thereby limiting the commonly associated hypotension, hypothermia, and coagulopathies. During the suboccipital craniectomy for evacuation of the EDH and repair of the sigmoid sinus, the patient required 18 units of blood replacement secondary to a large tear in the sigmoid sinus. During a separate craniotomy for evacuation of the SDH, the patient also developed diabetes insipidus, which increased the operative fluid replacement to 39 L. Despite these massive blood and fluid losses, the RIS limited the hypotension to less than 2 min and prevented hypothermia and the frequently associated coagulopathies. When used in a neurosurgical setting associated with massive blood and/or fluid losses, the RIS accomplishes three important objectives: (1) rapid infusion of intravenous fluids for maintaining perfusion pressure, (2) rapid warming of fluids despite high intravenous infusion rates of cold crystalloids, thereby preventing intraoperative hypothermia, and (3) continuous monitoring of infusion rates and totals.     

Glucagon-like peptide I enhances the insulinotropic effect of glibenclamide in NIDDM patients and in the perfused rat pancreas

OBJECTIVE: To investigate the acute effects of glibenclamide and glucagon-like peptide I (GLP-I) and their combination in perfused isolated rat pancreas and in patients with secondary failure to sulfonylureas. RESEARCH DESIGN AND METHODS: Rat islets were perfused with 10 nmol/l GLP-I in combination with 2 mumol/l glibenclamide. In human experiments, GLP-I (0.75 pmol. kg-1.min-1) was given as a continuous infusion during 240 min, while glibenclamide (3.5 mg) was administered orally. Eight patients participated in the study (age 57.6 +/- 2.7 years, BMI 28.7 +/- 1.5 kg/m2, mean +/- SE). In all subjects, blood glucose was first normalized by insulin infusion administered by an artificial pancreas (Biostator). RESULTS: GLP-I increased the insulinotropic effect of glibenclamide fourfold in the perfused rat pancreas. In human experiments, treatment with GLP-I alone and in combination with glibenclamide significantly decreased basal glucose levels (5.1 +/- 0.4 and 4.5 +/- 0.1 vs. 6.0 +/- 0.3 mmol/l, P < 0.01), while with only glibenclamide, glucose concentrations remained unchanged. GLP-I markedly decreased total integrated glucose response to the meal (353 +/- 60 vs. 724 +/- 91 mmol.l-1. min-1, area under the curve [AUC] [-30-180 min], P < 0.02), whereas glibenclamide had no effect (598 +/- 101 mmol.l-1. min-1, AUC [-30-180 min], NS). The combined treatment further enhanced the glucose lowering effect of GLP-I (138 +/- 24 mmol. l-1.min, AUC [-30-180 min], P < 0.001). GLP-I, glibenclamide, and combined treat-stimulated meal-induced insulin release as reflected by insulinogenic indexes (control 1.44 +/- 0.4; GLP-I 6.3 +/- 1.6, P < 0.01; glibenclamide 6.8 +/- 2.1, P < 0.01; combination 20.7 +/- 5.0, P < 0.001). GLP-I inhibited basal but not postprandial glucagon responses. Using paracetamol as a marker for gastric emptying rate of the test meal, treatment with GLP-I decreased gastric emptying at 180 min by approximately 50% compared with the control subjects (P < 0.01). CONCLUSIONS: In acute experiments on overweight patients with NIDDM, GLP-I exerted a marked antidiabetogenic action on the basal and postprandial state. The peptide stimulated insulin, suppressed basal glucagon release, and prolonged gastric emptying. The glucose-lowering effect of GLP-I was further enhanced by glibenclamide. This action may be at least partially accounted for by a synergistic effect of these two compounds on insulin release. Glibenclamide per se enhanced postprandial but not basal insulin release and exerted a less pronounced antidiabetogenic effect compared with GLP-I.     

The MITRE E3 family of models structure and results

A family of energy/economic/environmental (E³) models is presented as a mechanism for analysing national policy issues. The family consists of discrete models which are designed to be run in an integrated manner. The outputs of certain models provide the inputs to the next. This structure allows the analyst to readily incorporate an understanding of regional factors such as local energy prices, concerns over air quality, water availability, or attitudes towards construction of new energy facilities, into national assessments of energy policies. This paper reviews the analytic framework within which energy policy issues are currently addressed. The initial family of E³ models is described with the emphasis on the data linkages and feedback which are provided when these models are run sequentially. The ongoing MITRE research programme with the E³ family of models is presented and plans and opportunities for future work are outlined.     

Polymorphism of silica

A study of the stability relations of pure silica phases is described. It is shown that although cristobalite can be produced from pure quartz by heating it is not possible to produce tridymite in this fashion; a flux or mineralizer is required for tridymite formation and even in this case cristobalite is produced before any tridymite is observed. Thus it is concluded that the stability relations for the silica minerals proposed by Fenner are incorrect and that tridymite is not a stable phase in the pure silica system. This revised version was published online in November 2006 with corrections to the Cover Date.     

Advanced intelligent networks: now a reality

This paper looks first at the background to the development of intelligent networking concepts and then tracks this development to the advanced intelligent networks (AINs) of today. The network architecture and basic nodal functions are explained, and a brief review given of the essential intelligent network building blocks, namely the IN (intelligent network) call model and the enhanced CCITT No.7 signalling system. Typical intelligent network services are examined and the tutorial finishes with a review of the latest IN standards     

Postauricular chondrocutaneous flap in auricular reconstruction

We report an unusual case of a 1 cm papillary renal cell carcinoma arising from the outer surface of the free wall of a radiographically simple renal cyst. Most malignancies arising from the wall of a renal cyst are present along the inner surface, usually adjacent to underlying renal parenchyma. While this is a rare occurrence, it does reinforce the need to explore even small solid renal masses.     

The failure of an F/A-18 trailing edge flap hinge

During a flight over sea, the right-hand trailing-edge flap (TEF) from an RAAF F/A-18 separated. Although the flap was not recovered, the mode of failure suggested that the outboard hinge lug was first to fail. A fleet-wide inspection of the TEF outer hinge lugs disclosed two other cracked hinge lugs. Examination of these cracks revealed that they had propagated as the result of a combination of corrosion and fatigue, in that the corrosive environment appeared to have accelerated the fatigue crack growth rate. Laboratory experiments indicated that, in a salt solution, the 7050 aluminium alloy from which the lugs were manufactured is susceptible to corrosion fatigue and that the observed cracking matched that on the cracked lugs: corrosion fatigue was therefore suspected to have been a contributing factor in the unexpected failure. Quantitative fractography on the fatigue cracks, combined with several assumptions and deductions, including information about the failure size of the crack gained from witness marks found on the monoball bearing of the failed TEF, led to an estimate of the fatigue crack growth rate. This crack growth rate and the short service life clearly indicated the limitations of the then-current non-destructive inspection (NDI) technique, and a more sensitive inspection method was developed to assist in the maintenance of adequate RAAF flying hours between inspections. This failure investigation provided an excellent example of how fractography, laboratory experiments and NDI can be combined to determine a possible cause of failure and to establish remedial measures for the fleet.     

Evolution of the serum amyloid A (SAA) protein superfamily

The serum amyloid A (SAA) superfamily comprises a number of genes and proteins characterized from a range of mammalian species. The majority of members described to date are dramatically induced during the acute-phase response, suggesting an important short-term beneficial role in the response to tissue injury and inflammation. However, important disease associations have also been proposed for certain SAAs during chronic inflammation. The nomenclature of many of the superfamily members has been the result of comparisons with previously reported sequences implying disease association and/or functional relatedness between such members. The evolutionary relationships of the SAA superfamily members have been investigated by comparisons at both the amino acid and the nucleotide level. The results indicate that all members of the superfamily within a species have been undergoing concerted evolution. This has important implications in ascribing functions and disease associations to individual SAA superfamily members and indicates that designations should not be based on the extent of amino acid identity alone but should be made only following direct experimental observation of the proteins themselves.     

Sheep pulmonary adenomatosis: a unique model of retrovirus-associated lung cancer

Sheep pulmonary adenomatosis (SPA) is a contagious bronchiolo-alveolar carcinoma of sheep associated with an exogenous type D/B retrovirus known as jaagsiekte sheep retrovirus (JSRV). SPA represents a unique model for lung cancer, and studies on its aetiopathogenesis can provide further insight into the mechanisms of epithelial neoplasms.