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Purpose: Pre-hospital emergency anaesthesia is routinely used in the care of severely injured patients by pre-hospital critical care services. Anaesthesia, intubation, and positive pressure ventilation may lead to haemodynamic instability. The aim of this study was to identify the frequency of new-onset haemodynamic instability after induction in trauma patients with a standardised drug regime. Methods: A retrospective database analysis was undertaken of all adult patients treated by a physician-led urban pre-hospital care service over a 6-year period. The primary outcome measure was the frequency of new haemodynamic instability following pre-hospital emergency anaesthesia. The association of patient characteristics and drug regimes with new haemodynamic instability was also analysed. Results: A total of 1624 patients were included. New haemodynamic instability occurred in 231 patients (17.4%). Patients where a full-dose regime was administered were less likely to experience new haemodynamic instability than those who received a modified dose regime (9.7% vs 24.8%, p < 0.001). The use of modified drug regimes became more common over the study period (p < 0.001) but there was no change in the rates of pre-existing (p = 0.22), peri-/post-anaesthetic (p = 0.36), or new haemodynamic instability (p = 0.32). Conclusion: New haemodynamic instability within the first 30 min following pre-hospital emergency anaesthesia in trauma patients is common despite reduction of sedative drug doses to minimise their haemodynamic impact. It is important to identify non-drug factors that may improve cardiovascular stability in this group to optimise the care received by these patients. [ABSTRACT FROM AUTHOR]

The cyclin-dependent kinase inhibitors (CKIs) belong to a group of key cell cycle proteins that regulate important cancer drug targets such as the cyclin/CDK complexes. Gene defects in the INK4A/B CKI tumor suppressor locus are frequently associated with human cancers and we have previously identified similar defects in canine models. Many of the cancer-associated genetic alterations, known to play roles in mammary tumor development and progression, appear similar in humans and dogs. The objectives of this study were to characterize expression defects in the INK4 genes, and the encoded p16 family proteins, in spontaneous canine primary mammary tumors (CMT) as well as in canine malignant melanoma (CML) cell lines to further develop these models of spontaneous cancers. Gene expression profiles and characterization of p16 protein were performed by rtPCR assay and immunoblotting followed by an analysis of relevant sequences with bioinformatics. The INK4 gene family were expressed differentially and the genes encoding the tumor suppressor p16, p14, and p15 proteins were often identified as defective in CMT and CML cell lines. The altered expression profiles for INK4 locus encoded tumor suppressor genes was also confirmed by the identification of similar gene defects in primary canine mammary tumor biopsy specimens which were also comparable to defects found in human breast cancer. These data strongly suggest that defects identified in the INK4 locus in canine cell lines are lesions originating in spontaneous canine cancers and are not the product of selection in culture. These findings further validate canine tumor models for use in developing a clear understanding of the gene defects present and may help identify new therapeutic cancer treatments that restore these tumor suppressor pathways based on precision medicine in canine cancers. [ABSTRACT FROM AUTHOR]

p16 is an important tumor suppressor gene encoded by the INK4A/ARF/INK4B gene locus that is conserved in humans, rodents, and canids. p16 regulates cell cycle in early G1 phase inhibiting transition out of cell cycle from G1/S phase by regulating a multi-protein control complex. p16-associated proteins, cyclin D, CDK4, and CDK6, experience expression level decreases or do not change during cell differentiation and quiescence in contrast to constant p16 expression in post-proliferative cell phases. We hypothesized that p16 has alternate binding partners, other than classical proliferation-associated proteins such as CDKs, in these post-proliferative cell phases. Using co-immunoprecipitation, we have identified 14-3-3σ as a potential alternate binding partner for p16 in quiescent post-proliferative canine mammary cancer cells. Additionally, expression of 14-3-3σ was maintained as fibroblasts exit cell cycle and differentiate to adipocytes simultaneously with continued expression of p16. Based on these results, we suggest that 14-3-3σ protein may be an alternative binding partner for p16 active during cell quiescence and may associate with p16 during cell differentiation. [ABSTRACT FROM AUTHOR]

In small amplitude oscillatory shear flow, we now universally represent the response of a viscoelastic fluid as a complex quantity, which we call 'complex viscosity.' This short piece deepens our understanding of the origins of the complex viscosity and of the man who coined this term, now widely used in rheology. [ABSTRACT FROM AUTHOR]

Mammary cancer is among the most prevalent canine tumors and frequently resulting in death due to metastatic disease that is highly homologous to human breast cancer. Most canine tumors fail to raise effective immune reactions yet, some spontaneous remissions do occur. Hybrid canine dendritic cell-tumor cell fusion vaccines were designed to enhance antigen presentation and tumor immune recognition. Peripheral blood-derived autologous dendritic cell enriched populations were isolated from dogs based on CD11c expression and fused with canine mammary tumor (CMT) cells for vaccination of laboratory Beagles. These hybrid cells were injected into popliteal lymph nodes of normal dogs, guided by ultrasound, and included CpG-oligonucleotide adjuvants. Three rounds of vaccination were delivered. Significant IgG responses were observed in all vaccinated dogs compared to vehicle-injected controls. Canine IgG antibodies recognized shared CMT antigens as was demonstrated by IgG-recognition of three unrelated/independently derived CMT cell lines, and recognition of freshly isolated, unrelated, primary biopsy-derived CMT cells. A bias toward an IgG2 isotype response was observed after two vaccinations in most dogs. Neither significant cytotoxic T cell responses were detected, nor adverse or side-effects due to vaccination or due to the induced immune responses noted. These data provide proof-of-principle for this cancer vaccine strategy and demonstrate the presence of shared CMT antigens that promote immune recognition of mammary cancer. [ABSTRACT FROM AUTHOR]

Bovine viral diarrhea virus (BVDV) is an economically important cattle pathogen with worldwide distribution. Besides the segregation of noncytopathic and cytopathic (CP) biotypes, BVDV exists as two genotypes. Both genotypes cause similar disease, and the majority of type-2 BVDV (BVDV-2) is no more virulent than type-1 viruses (BVDV-1). However, some BVDV-2 viruses are hypervirulent and causative reagents of a lethal disease called severe acute bovine viral diarrhea. Amino acid (aa) sequence analysis shows that the majority of hypervirulent BVDV-2 isolates contains an extra 16 aa peptide (-SSCPVPFDPSCHCNYF-) at C-terminal NS2 region. In this study, we investigated the flexibility of the corresponding NS2 region of BVDV-1 for tolerance of this peptide insertion and its effect on viral pathogenicity. Based on an infectious cDNA clone of BVDV-1 SD-1, a cDNA clone called pASD1-IN was constructed with insertion of the 16 aa peptide in the corresponding NS2 site. In vitro transcription and transfection of Madin-Darby bovine kidney (MDBK) cells resulted in the generation of infectious chimeric virus termed ASD1-IN. ASD1-IN does not show CP effect on MDBK cells and is similar to ASD1 in viral growth. Furthermore, ASD1-IN shows an NS2-3 processing pattern similar to ASD1. These results reveal that insertion of the 16 aa peptide at C-terminal NS2 of BVDV-1, at least for SD-1, has no effect on viral replication and NS2-3 processing in MDBK cells. [ABSTRACT FROM AUTHOR]

The Hand Hygiene Liaison Group and Epic Projects ( Pratt et al., J Hosp Infect 47[Suppl A], 2001) have asked specifically for further trials of educational interventions to improve hand decontamination compliance and infection control in the hospital setting. This study investigates the efficacy of a ‘clean practice protocol’ (CPP), derived from international guidelines, to improve compliance of infection-control practices by surgical teams in a large UK teaching hospital. The key infection-control activities were summated to form the CPP presented here. An undisclosed infection-control audit of consultant-led ward-rounds from breast, gastrointestinal, vascular, urological, and intensivecare departments was performed. The audit results were presented to the surgical teams, after which an education/awareness program was implemented. A repeat undisclosed audit was performed 3 months later. In both audits, infection-control activities were recorded together with consultation time and any patient infective complications. The surgical teams performed as follows in the initial audit: hand decontamination (28% of consultations), correct use of gloves (2%), instrument cleaning (0%), garment contamination (49%), and notes contamination (34%). Introduction of the CPP education program significantly improved hand decontamination to 87% (p < 0.0001), the correct use of gloves/aprons to 50% (p < 0.0001), and overall infection-control practice from 63% to 89% (p < 0.05). The introduction of the CPP significantly improved compliance of hand decontamination, correct usage of gloves and aprons, and overall infection-control in a large teaching hospital. The CPP is a highly effective auditing and educational tool that can be readily adapted for use in hospitals globally to monitor and improve infection-control practices. [ABSTRACT FROM AUTHOR]

Using a 141 F2 population generated from maize inbred B64 × teosinte Zea nicaraguensis cross, quantitative trait loci (QTLs) controlling aerenchyma formation in roots under non-flooding drained soil conditions were identified. Seedlings of Z. nicaraguensis formed clear aerenchyma in the cortex of adventitious roots in non-flooding conditions, whereas the maize inbred line B64 did not. In the F2 population, the capacity to develop aerenchyma exhibited wide and continuous variation, suggesting the trait was controlled by multiple genes. A linkage map was developed using 85 SSR markers, covering 1,224 cM across all ten chromosomes. Composite interval mapping analysis revealed that four QTLs for aerenchyma formation under non-flooding conditions were located to two regions of chromosome 1 (identified as Qaer1.02-3 and Qaer1.07), chromosome 5 ( Qaer5.09) and chromosome 8 ( Qaer8.06-7), and these explained 46.5% of the total phenotypic variance. The multiple interval mapping approach identified additional QTLs on chromosomes 1 ( Qaer1.01) and 5 ( Qaer5.01). Using these results, it may be possible to use SSR markers linked to aerenchyma formation in a marker assisted selection approach to introduce aerenchyma formation in drained soil conditions into maize for the eventual development of flooding tolerant maize hybrids. [ABSTRACT FROM AUTHOR]

Objective:Oral supplements of fenugreek (Trigonella foenum graecum) seeds (Fen) have been shown to treat glucose and lipid homeostasis in several metabolic disorders; however, its ability to alleviate obesity-associated pathologies is not known. The main objective of this study was to evaluate the effect of Fen in Zucker obese rats (Ob), an animal model of obesity and related disorders, such as dyslipidemia and hepatic steatosis.Methods:Female Zucker (6-week-old) Ob and lean (Ln) rats were randomly grouped (n=8 rats/group) to receive either basal or 5% Fen-supplemented AIN-93G diets for 8 weeks, and then were euthanized. Histopathology and biochemical parameters in the liver together with plasma biochemistry were assessed.Results:Obese rats had significantly higher (P<0.05) body and liver weight, as well as plasma insulin, lactate, cholesterol, triglyceride and tumor necrosis factor (TNF)-α compared to their Ln counterparts. Fen significantly reduced (P<0.05) the liver-weight of Ob rats in comparison to Ob rats fed basal diet (Control), while no effect was observed in the Ln rats. Fen treatment resulted in a lower P-value (P<0.05). In addition, Ob rats on Fen-supplemented diets had fasting plama cholesterol and TNF-α levels, and significantly higher (P<0.05) triglycerides in comparison to the control rats. Hepatic triglyceride level was significantly lower (P<0.05) in Ob rats fed Fen supplemented diets in comparison to control. The levels of bound and soluble liver TNF-α (26 and 17 kDa, respectively) and TNF receptor-II (TNFR-II, 75 kDa) proteins were significantly lower (P<0.05) in Ob than in Ln rats. Fen significantly lowered (P<0.05) both the soluble and bound forms of TNF-α protein while significantly elevating (P<0.05) TNFR-II in the livers of Ob rats compared to Ob Controls.Conclusion:These results demonstrate unequivocally that in a short-term preclinical evaluation, dietary Fen supplementation reduced the triglyceride accumulation in the liver, a hallmark feature of hepatic steatosis without affecting the plasma insulin or glucose levels in Zucker obese rats and suggest that TNF-α may play an important role in this process.International Journal of Obesity (2006) 30, 1298–1307. doi:10.1038/sj.ijo.0803254; published online 14 February 2006 [ABSTRACT FROM AUTHOR]

Purpose: An audit study investigated the pilot use of regional nerve block analgesia (as an alternative to sedative/opiate, general or central neuraxial anesthesia) performed by radiologists with the assistance of imaging techniques during complex prolonged angiography. Methods: Radiologists were trained by anesthetic consultants to administer and use lower limb peripheral nerve block for difficult prolonged angioplasty procedures for patients with severe lower limb rest pain who were unable to lie in the supine position. In a pilot study 25 patients with limb-threatening ischemia received sciatic and femoral nerve blockade for angioplasty. The technique was developed and perfected in 12 patients and in a subsequent 13 patients the details of the angiography procedures, peripheral anesthesia, supplementary analgesia, complications, and pain assessment scores were recorded. Pain scores were also recorded in 11 patients prior to epidural/spinal anesthesia for critical ischemic leg angioplasty. Results: All patients with peripheral nerve blockade experienced a reduction in their ischemic rest pain to a level that permitted angioplasty techniques to be performed without spinal, epidural or general analgesia. In patients undergoing complex angioplasty intervention, the mean pain score by visual analogue scale was 3.7, out of a maximum score of 10. Conclusions: The successful use of peripheral nerve blocks was safe and effective as an alternative to sedative/opiate, epidural or general anesthesia in patients undergoing complex angiography and has optimized the use of radiological and anesthetic department resources. This has permitted the frequent radiological treatment of patients with limb-threatening ischemia and reduced delays caused by the difficulty in enlisting the help of anesthetists, often at short notice, from the busy operating lists. [ABSTRACT FROM AUTHOR]

Morphological and anatomical factors such as aerenchyma formation in roots and the development of adventitious roots are considered to be amongst the most important developmental characteristics affecting flooding tolerance. In this study we investigated the lengths of adventitious roots and their capacity to form aerenchyma in three- and four-week-old seedlings of two maize ( Zea mays ssp. mays, Linn.) inbred accessions, B64 and Na4, and one teosinte, Z. nicaraguensis Iltis & Benz (Poaceae), with and without a flooding treatment. Three weeks after sowing and following a seven day flooding treatment, both maize and teosinte seedlings formed aerenchyma in the cortex of the adventitious roots of the first three nodes. The degree of aerenchyma formation in the three genotypes increased with a second week of flooding treatment. In drained soil, the two maize accessions failed to form aerenchyma. In Z. nicaraguensis, aerenchyma developed in roots located at the first two nodes three weeks after sowing. In the fourth week, aerenchyma developed in roots of the third node, with a subsequent increase in aerenchyma in the second node roots. In a second experiment, we investigated the capacity of aerenchyma to develop in drained soil. An additional three teosinte species and 15 maize inbred lines, among them a set of flooding-tolerant maize lines, were evaluated. Evaluations indicate that accessions of Z. luxurians (Durieu & Asch. Bird) and two maize inbreds, B55 and Mo20W, form aerenchyma when not flooded. These materials may be useful genetic resources for the development of flooding-tolerant maize accessions. [ABSTRACT FROM AUTHOR]

Screening of synthetic retinoids for activity against prostate carcinoma cell lines has identified antagonists of retinoic acid receptors (RARs) as potent growth inhibitors (Hammond et al, 2001, Br J Cancer 85, 453-462). Here we report that 5 days of exposure to a high-affinity pan-RAR antagonist (AGN194310) abolished growth of prostate carcinoma cells from 14 out of 14 patients, with half-maximal inhibition between 200 and 800 nM. It had similar effects (at approximately 250 nM) on the prostate carcinoma lines LNCaP, DU-145 and PC-3. AGN194310 inhibited the growth of normal prostate epithelium cells less potently, by 50% at approximately 1 microM. The growth of tumour cells was also inhibited more than that of normal cells when RARbeta together with RARgamma, but not RARalpha alone, were antagonised. Treatment of LNCaP cells with AGN194310 arrested them in G1 of cell cycle within 12 h, with an accompanying rise in the level of p21(waf1). The cells underwent apoptosis within 3 days, as indicated by mitochondrial depolarisation, Annexin V binding and DNA fragmentation. Apoptosis was caspase-independent: caspases were neither cleaved nor activated, and DNA fragmentation was unaffected by the pan-caspase inhibitor Z-VAD-FMK. The ability of AGN 194310 to induce apoptosis of prostate cancer cells and its differential effect on malignant and normal prostate epithelial cells suggests that this compound may be useful in the treatment of prostate cancer. [ABSTRACT FROM AUTHOR]

A comprehensive study of the suitability of sheets of alloy 1441 of the Al – Cu – Mg – Li system for the production of long-life airplane fuselages is described. The alloy has been used in the Be 103 boatplane airframe and is tested for use in the new business-class airplane of the A. N. Tupolev Aircraft Scientific-and-Engineering Company (ANTK). Sheets of alloy 1441 including thin ones with a thickness of 0.5 mm are manufactured by cold coil rolling. As compared to traditional deformable alloys of the Al – Cu – Mg system, alloy 1441 has a diminished density and an elevated modulus of elasticity at a comparable level of strength. Researchers in Russia (GP GNTs VIAM) and in the USA (LaRC, NASA) studied the tensile mechanical properties, the fracture toughness, the impact toughness, the fatigue resistance, and the growth rate of fatigue crack in sheets fabricated from alloy 1441. Researchers of the A. N. Tupolev ANTK fabricated fuselage panels with sheathing from alloy 1441 and stringers from high-strength aluminum alloy V95. The panels were tested in the ANTK and in the LaRC by the method of internal pressure by pulse-cycle simulation of the surface conditions of the airplane. [ABSTRACT FROM AUTHOR]

We have evaluated under laboratory validation conditions and in an extensive field trial the behaviour of an ambulatory monitoring device that is capable of recording both by the Korotkoff-sound and oscillometric methods in a single cuff deflation (TM2421: A&D Co, Tokyo, Japan). The effects of subject age and blood pressure (BP) level on the accuracy and field reliability of the two methods implemented in the device have been determined. In the validation phase, automatic BP measurements were compared with readings by two trained observers in 96 subjects, and the results compared with the AAMI criteria for automatic BP monitors. In the field trial phase, the performances of Korotkoff-sound and oscillometric methods over a 24-h period of ambulatory BP monitoring were compared in 515 subjects, with analysis of the agreement between the two methods in patients where both provided satisfactory recordings. In the validation phase, the Korotkoff-sound method gave satisfactory results for both systolic and diastolic BP, but the oscillometric technique narrowly failed to meet the AAMI criteria for the measurement of either systolic or diastolic BP. In the field trial, the K-sound method failed to record BP accurately in 12% of subjects whereas the oscillometric method was successful in all of these. Where both methods provided technically adequate records, agreement between mean values for each method was close. In 18% of patients, the availability of the oscillometric measurement as a 'back-up' method for the K-sound method significantly improved the number of available measurements in the monitoring period, which should result in improved accuracy and reproducibility of the ambulatory mean values. [ABSTRACT FROM AUTHOR]

This study was carried out to ascertain the value of ambulatory blood pressure monitoring (ABPM) in the diagnosis and treatment of hypertension in routine clinical practice. ABPM was performed during the daytime hours in 410 patients believed to be hypertensive after at least three measurements by their physician and one measurement by a nurse in a hypertension clinic. The diagnosis was confirmed in 70% of patients when 90 mm Hg diastolic blood pressure (BP) was used as the upper limit of normal, and 86.3% when 85 mm Hg was used. In 204 patients who were reviewed 5 years later there were 108 on medical treatment. This reduced diastolic pressure from a mean of 100.6 ± 8.8 to 85.7 ± 8.8 mm Hg. However, in 30% of patients the diastolic pressure was still above 90 mm Hg. In the 49 patients with isolated clinic hypertension (ICH), who had remained untreated, diastolic pressure increased from 84.0 ± 4.8 to 88.1 ± 8.4 mm Hg over the 5 years. In 19 of these the level exceeded 90 mm Hg. ABPM therefore improves diagnostic accuracy and prevents treatment of patients with ICH. This condition, however, requires follow-up since BP tends to rise with time in some patients. The audit also identified patients who had had a suboptimal response to medical treatment. [ABSTRACT FROM AUTHOR]

The phase-space kinetic theory for polymeric liquid mixtures has been further developed for molecular models without internal constraints. The theory provides expressions for the mass, momentum, and energy fluxes, each of which may in general be influenced by concentration, velocity, and temperature gradients. To illustrate the use of these results, the thermal conductivity for a dilute polymer solution is derived; the FENE dumbbell model is used to describe the mechanical behavior of the polymer chains. The Hookean dumbbell results can be obtained by letting the 'finite extensibility parameter' b tend to infinity. [ABSTRACT FROM AUTHOR]

It has been found that for some dilute polymer solutions the dynamic viscosity at very high frequencies is less than the zero-shear-rate solvent viscosity. Such an effect cannot be explained by the usual kinetic theories using bead-spring-rod models. Here we examine several modifications of the kinetic theories that might be expected to explain the experimental facts. [ABSTRACT FROM AUTHOR]

Cellular survival results for late-S Chinese hamster V79 cells exposed to triads of protons of variable mean separations are reported. The data are analyzed within the framework of the Theory of Dual Radiation Action [8]. This analysis provides a new estimation of the function γ( x) representing the probability of two energy transfers separated by the distance x to produce a lesion. In agreement with an earlier study [6] involving pairs of deuterons, it is concluded that: a) the process of lesion formation depends strongly on the relative separation of energy deposition events, and b) intratrack and intertrack lesions correspond to substantially different separations of pairwise energy transfers. [ABSTRACT FROM AUTHOR]

The objective of this study was to establish a method by which trophectodermal cells originating from individual preimplantation bovine embryos could be perpetuated in monolayer culture. A single, Day-11 bovine embryo collected nonsurgically from a mixed-breed beef cow was cultured in Ham's F10 medium supplemented with fetal bovine serum, sodium pyruvate, insulin and epidermal growth factor. After 13 d in culture the embryo had adhered to the surface of the plastic culture vessel and a monolayer covering 0.3 cm had developed in the manner of a tissue explant. The monolayer was successfully dispersed using trypsin-EDTA and the cells were passaged Expansion to a 25-cm flask was achieved by the 4th passage. By passaging cultures at a dilution ratio of 1∶2, cells were maintained for 38 passages before growth slowed. Transfers beyond the 44th passage were unsuccessful. The cell line, designated BE-13, was successfully frozen and thawed at the 9th, 12th, 15th, and 20th passages. The cell line contains both mono- and binucleate cells with a prominent rough endoplasmic reticulum characteristic of ruminant trophoblast cells. Susceptibility to eight bovine viruses was demonstrated. Such cell lines may provide inexpensive systems for the study of trophoblast metabolism and for investigation of the role of the trophoblast in the pathogenesis of selected bovine abortifacient diseases. Because of their range of viral susceptibility, these cells might also be useful for diagnostic purposes. [ABSTRACT FROM AUTHOR]

This paper describes a technique for transforming functional programs that repeatedly traverse a data structure into more efficient alternatives that do not. The transformation makes essential use of lazy evaluation and local recursion (such as provided by letrec, or its equivalent) to build a circular program that, on one pass over the structure, determines the effects of the individual traversals and then combines them. [ABSTRACT FROM AUTHOR]

The fine structure of Theileria-lymphoblast relationship was studied using cultured bovine lymphoblastoid cells infected with Theileria parva, T. lawrencei, or T. annulata. The major findings of this study were: (a) the presence of a very active Golgi complex with the associated annulate lamellae; (b) the presence of cytoplasmic microtubules which joined the parasites and host cell centriole during lymphoblast mitosis; and (c) the absence of morphological evidence to suggest that the host cell developed a reaction to the parasitic presence. The significance of these findings is discussed. [ABSTRACT FROM AUTHOR]

The effects of oxidized fat components (free fatty acids from the distillable nonurea adductable fraction) isolated from heated corn oil or heated olive oil on the morphology and growth of heart cells in primary culture were investigated. The free fatty acid fractions isolated from the fresh fats served as controls. Different concentrations of the fat fractions (20, 60, and 100 μg/ml) were added to the medium in the form of an emulsion with bovine serum albumin (Fraction V, poor in unesterified fatty acids). In the cell cultures treated with heated fats, intracellular lipid accumulation, increased cytoplasmic vacuolization, mitotic aberrations, pyknotic cells, and decreased mitosis were observed and were more pronounced in the case of the heated olive oil. These cytotoxic effects increased with higher concentrations of heated fats in the medium. The fresh fats also produced intracellular lipid accumulation, reductions in mitosis, and changes in the nucleus and cytoplasm, at the higher levels. These effects were greater in fresh olive oil-treated cultures. These observations indicate that oxidized fat components interfere physically or biochemically with normal cell functions resulting in pathological changes. [ABSTRACT FROM AUTHOR]

Three recent wild-type H1N1 influenza virus isolates (A/USSR/90/77, A/Fiji/15899/83 and A/Firenze/13/83) replicated poorly in organ cultures of ferret bronchial tissue compared with the replication of an H3N2 wild-type virus (A/England/939/69). All four viruses replicated well in nasal turbinate tissue. Examination of one H1N1 virus (A/USSR/90/77) in vivo showed heavy infection in the upper respiratory tract of ferrets but little in the lower respiratory tract. These results raise the possibility that the mildness of human influenza arising from the H1N1 strains may be due to lack of capacity to attack the lower respiratory tract as well as the presence of antibody in previously exposed persons. [ABSTRACT FROM AUTHOR]

In contrast to its abundant replication in ferret nasal epithelium in vivo and in vitro, comparable to that of the virulent strains, the attenuated influenza virus A/PR/8/34 produced much lower yields than the virulent strains in organ cultures of bronchial epithelium agreeing with its relative inability to infect the lower respiratory tract of ferrets. The replication of another attenuated strain showed different temperature characteristics in bronchial epithelium to that in nasal turbinate epithelium. [ABSTRACT FROM AUTHOR]

This paper describes a computer-based system for the on-line experimental use of musical stimuli. The system is in two sections. The first records in digital form two successive monophonie keyboard performances and combines them into a two-part musical stimulus consisting of bass and treble melodic lines. This musical stimulus can be modified in one or more ways by means of an editing program. The second part of the system presents the modified stimulus to the subject and records his reaction time to particular target notes. The system can be expanded to allow the merging of a larger number of melodic lines into a single polyphonic form or can be modified to produce precisely controlled two-channel tonal stimuli. [ABSTRACT FROM AUTHOR]

A summary is given of some recent attempts to relate the results of the kinetic theory of rigid and flexible macromolecules to continuum mechanics results. [ABSTRACT FROM AUTHOR]

It has been shown that the Oldroyd 6-constant model is incapable of describing the time-dependent rheological behavior of dilute suspensions of rigid dumbbells with Brownian motion. It is, however, possible to introduce two new terms into Oldroyd's equation, so that the time-dependent viscoelastic flows can be described correctly through second order; furthermore stationary flows can be described through the third order. Es wurde festgestellt, daß die Gleichung von Oldroyd nicht ausreicht, um das zeitabhängige rheologrsche Betragen verdünnter Suspensionen von starren Hanteln zu beschreiben. Es ist aber möglich, zwei neue Glieder in die Oldroydsche Gleichung einzuführen, um die zeitabhängigen viskoelastischen Strömungen von Hantelsuspensionen bis zur zweiten Ordnung richtig beschreiben zu können; außerdem können die stationären Strömungen bis zur dritten Ordnung angegeben werden. [ABSTRACT FROM AUTHOR]

The blood pressure (BP) lowering effect of low doses of antihypertensive agents is not usually explored because of the difficulty in detecting small changes in BP. Since ambulatory blood pressure monitoring in a cross-over trial design can reliably detect differences of 5 mmHg with less than 20 subjects, we have used this technique to assess the dose-response curve of a new β-blocker, carvedilol. Twenty subjects were enrolled after diagnostic ambulatory BP monitoring had shown a day-time average diastolic BP of over 90 mmHg. Three doses of carvedilol (6.25, 12.5 and 25 mg daily) and placebo were then given double-blind in random order for periods of 4 weeks each. No period effects were detected. The antihypertensive effect was statistically significant at doses of 12.5 mg and 25 mg daily. There was, however, no evidence that 25 mg/day produced the peak effect. The lowest dose (6.25 mg/day) produced a small fall in both systolic and diastolic BP but neither of these were significant. We conclude that doses of 12.5 and 25 mg carvedilol once a day are adequate for the treatment of hypertension. [ABSTRACT FROM AUTHOR]