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The determination of the earth pressure coefficient in a natural clay deposit is a problem of considerable significance in geotechnical engineering. While the methods for evaluation of are reliable for normally consolidated soils, significant difficulties still exist in evaluating in overconsolidated clays, given that it is influenced by the stress history of the material, together with the age, structure, mineralogical composition and depositional environment. Indeed, some of these factors are responsible for the soil becoming anisotropic. The existing framework for prediction of in overconsolidated soils does not account for any influences caused by anisotropy. The work reported in this paper evaluates the validity of a revised relationship between and OCR (overconsolidation ratio) using data obtained from laboratory investigations. The tests were performed on reconstituted and undisturbed samples of Belfast Upper Boulder Clay, London Clay and Gault Clay. Tests were also performed on reconstituted samples of kaolin. The values of were determined using various approaches, including on-sample measurements. The results have confirmed that reliable predictions of can be made using the proposed relationship. [ABSTRACT FROM AUTHOR]

To gain knowledge of visual specializations influencing the behavior of white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)), we examined gross eye characteristics, structural organization of the retina, and the density and distribution of cone photoreceptors. White-tailed deer possess ocular features similar to other ungulates including a horizontal slit pupil, reflective tapetum lucidum, typical retinal structure, and medium wavelength sensitive cone photoreceptors concentrated in a horizontal visual streak. The tapetum was found to cover the superior portion of the eye and overlapped the horizontal visual streak. Comparisons between fawns and adults did not reveal any differences in retinal thickness, retinal nuclei counts, or cone photoreceptor counts. While M-cones had increased density in the visual streak, S-cones were distributed evenly across the entire retina. Schematic eye calculations of a 0.5-year-old deer indicated a hyperopic eye (+7.96) with a F/# ranging from 5.55 to 1.39 for pupil diameters of 3 to 12 mm. As expected for a crepuscularly active prey species, the visual system of white-tailed deer is specialized for sensitivity in low-light conditions and detection of predators. Afin de connaître les spécialisations visuelles qui influencent le comportement du cerf de Virginie (Odocoileus virginianus (Zimmermann, 1780)), nous avons examiné les caractéristiques grossières de l’œil et l’organisation structurale de la rétine et déterminé la densité et la répartition des cônes photorécepteurs. Les cerfs de Virginie possèdent des caractéristiques oculaires semblables à celles d’autres ongulés, en particulier une pupille à fente horizontale, un tapetum lucidum réfléchissant, une structure rétinienne typique et des cônes photorécepteurs sensibles aux longueurs d’onde moyennes concentrés dans une bande visuelle horizontale. Le tapetum couvre la portion supérieure de l’oeil et recouvre la bande visuelle horizontale. Des comparaisons entre les faons et les adultes ne montrent aucune différence dans l’épaisseur de la rétine, le dénombrement des noyaux rétiniens, ni le dénombrement de cônes photorécepteurs. Alors que les cônes M ont une densité plus élevée dans la bande visuelle, les cônes S se répartissent uniformément sur toute la rétine. Des calculs schématiques de l’œil d’un cerf âgé de 0,5 an indiquent que l’œil est hypermétrope (+7,96) avec une valeur de F/# variant de 5,55 à 1,39 pour des diamètres de pupille de 3 à 12 mm. Comme on peut s’y attendre chez une espèce active au crépuscule, le système visuel du cerf de Virginie se spécialise pour une sensibilité aux conditions de lumière basses et pour la détection des prédateurs. [ABSTRACT FROM AUTHOR]

Forty cases of oral cavity non-Hodgkin's lymphoma (NHL) were evaluated for sex, age, location, clinical presentation, and World Health Organization (WHO) histological subtype. Fifty-three percent were female and the mean age was 71. The upper jaw (maxilla or palatal bone), mandible, palatal soft tissue, and vestibule and gingivae (maxillary or mandibular soft tissue involvement only) were, respectively, the most common locations. Swelling, ulceration, and radiographic destruction of bone were the most frequent signs. Most of the lymphomas were of B cell lineage (98%), and the majority of these B cell lymphomas (58%) were histologically subtyped as diffuse large B cell lymphoma, which is considered to have an aggressive clinical course. An immunohistochemical panel was used in the majority of cases to confirm the lineage and to help characterize the subtype. B and T cell specific markers were used to show lineage of the neoplastic cells. Additional markers were used to help confirm specific subtypes that characteristically show specific positivity to some of these antibodies. Molecular studies to detect monoclonal immunoglobulin heavy chain (IgH) gene rearrangements and Bcl-1 and Bcl-2 gene translocations were performed in cases in which the diagnosis was in question. The current WHO classification is also reviewed in detail. [ABSTRACT FROM AUTHOR]

Interferon lambda-1 (IFN-λ1), the prototype Type-III interferon, has antiviral functions similar to those of the Type-I interferons, IFN-α and IFN-β. However, IFN-λ1 is capable of signaling through almost all STAT molecules and so it is possible that it may have novel immunoregulatory functions in addition to antiviral ones. From a range of chemokines tested, IFN-λ1 elevated mRNA levels of only ‘Monokine induced by IFN-gamma’ (MIG/CXCL9), ‘IFN-gamma inducible protein-10’ (IP-10/CXCL10) and ‘IFN-gamma inducible T-cell α chemoattractant’ (I-TAC/CXCL11) from human peripheral blood mononuclear cells. As their names suggest, these chemokines are also induced by IFN-γ, the only member of the Type-II interferon family. This action of IFN-λ1 did not depend on intermediate induction of IFN-γ and is therefore, likely to be independent of IFN-γ. Further, our results suggest that donors responded to IFN-λ1 stimulation either ‘early’ or ‘late’. Overall the action of IFN-λ1 was similar to that previously reported for IFN-γ and may invite more detailed investigation of the role of IFN-λ1 at the innate/adaptive interface.Genes and Immunity (2007) 8, 177–180. doi:10.1038/sj.gene.6364372; published online 25 January 2007 [ABSTRACT FROM AUTHOR]

OBJECTIVE: To compare the potential risk of blood contamination of the surgeon's conjunctiva during tonsillectomy using disposable bipolar diathermy and reusable monopolar diathermy. DESIGN: A prospective, single-blind, randomized, controlled trial. METHODS: Elective tonsillectomy was performed using either disposable bipolar diathermy or reusable monopolar diathermy. The operating surgeon wore a ViewsafeTM protective eyeshield which was later examined under an operating microscope by a blinded observer and the number of blood spots counted. RESULTS: One hundred and sixty-eight patients were enrolled. The relative risk of conjunctival contamination of the surgeon using disposable bipolar diathermy was 2.8 times that with reusable monopolar diathermy (chi-squared test, p < 0.0005). A previous history of peritonsillar abscess and additional adenoidectomy were associated with increased blood splatter. CONCLUSION: The use of disposable bipolar diathermy for haemostasis during tonsillectomy poses a greater risk of conjunctival contamination for the surgeon than using reusable monopolar diathermy. [ABSTRACT FROM AUTHOR]

Burn pain can cause psychologic and functional difficulties, and is difficult to predict from wound depth. The initial painful stimulation of nerve endings by the burn with continued painful stimuli result in peripheral and central mechanisms causing amplification of painful stimuli, and the development of chronic pain syndromes that can be difficult to treat. In order to assess the effect of analgesic interventions it is essential to measure the patient's pain in a simple and reproducible manner. A number of tools exist for this measurement, ranging from longer and more detailed techniques such as the McGill pain questionnaire most suited to relatively stable pain, to visual analogue scores and picture-based scores for children. Pain management begins with the acute injury, with initial measures such as cooling of the burn and use of inhalational agents such as oxygen/nitrous oxide mixtures. On arrival in hospital, for any but trivial burns, intravenous opioids are appropriate and should be administered as small intravenous boluses titrated against effect. Following the initial resuscitation, pain may be divided into background pain and that associated with procedures. These often require different analgesic interventions. Background pain may be treated with potent intravenous opioids by infusion or patient controlled analgesia and then on to oral, less potent opioids, followed by other oral analgesics. Often drug combinations work best. More severe procedural pain may be treated with a variety of interventions from a slight increase in therapy for the background pain to more potent drugs, local blocks, or general anaesthesia. In addition to drug-based methods of managing burn pain, a number of nonpharmacologic approaches have been successfully employed including hypnosis, auricular electrical stimulation, massage, and a number of cognitive and behavioural techniques. [ABSTRACT FROM AUTHOR]

Human T-cell hybrids were constructed from an HGPRT-negative mutant of the acute lymphoblastoid leukaemia cell-line CEM and an uncloned population of T cells from donor SW (SW-T; partner cell) known to have a strong specificity for the autologous Epstein-Barr virus (EBV)-transformed B cell, SWEBV, The resulting hybrids, 1A9, 1D12 and 2C8, were shown not to be cytotoxic to SWEBV, nor did they have natural killer-like (NK) activity. However, when presented with the target SWEBV in a mixed lymphocyte reaction (MLR), all of the hybrids rapidly increased their rate of proliferation by up to a factor of seven. Hybrid 1D12 also produced interleukin-2-like material (IL2) under these conditions. The hybrids did not react with the autologous PHA-blasts (SWPHA), nor with various unrelated targets. When tested against a bank of EBV-transformed B-cell targets, it was observed that the human T-cell hybrids 1A9 and 2C8 responded only to those targets bearing the antigen HLA Bw35, This response could be blocked by treating the target with the monoclonal antibody W6/32, specific for a shared determinant of the HLA-A, -B and -C antigens. Similarly, the human T-cell hybrid 1D12 reacted only against those targets bearing the antigen HLA DrW2, and this activity could be blocked by the monoclonal antibody DA6,231, specific for a common region of the HLA-DR and SB antigens. Thus, human T-cell hybrids can be produced which exhibit HLA-restricted responses to antigenic stimulation. [ABSTRACT FROM AUTHOR]

The ability of LAK cells and/or IL-2 to affect the course of an established T cell response was examined in a delayed-type hypersensitivity (DTH) model, IL-2 greatly increased the magnitude of the response at 24 h. while LAK cells alone had no effect. The administration of LAK cells and IL-2 together also had no effect on the magnitude of the DTH response, demonstrating that LAK cells were able to remove the enhancement seen with IL-2 alone. The presence of LAK cells reduced the serum half-life of IL-2 significantly, but not to an extent able to account for the observed loss of IL-2 induced DTH enhancement. IL-2 administration influenced cell phenotypes in the spleen and draining lymph nodes (DLN), as well as increasing splenic weight; the additional presence of LAK cells markedly altered these effects of IL-2 in the spleen (but not the DLN). Taken together., these results suggest that LAK cells interact with activated T-cells within the immune system and modulate their function. [ABSTRACT FROM AUTHOR]

Presents abstracts on surgery. 'Increased TNF-alpha2 microsatellite allele frequency in Barrett's adenocarcinoma,' by H. Kasem, G. Gallagher, H.-H., Oh and R.C., Stuart; 'p53 and p16 gene therapy results in killing of pancreatic cancer cells,' by P. Ghaneh, M. Humphreys, W. Greenhalf, N. Lemoine and J.P. Neoptolemos; 'Differential gene expression in adenocarcinoma of the oesophagus,' by A.G.K. Li, P.A. Robinson, A.F. Markham and P.J., Guillou.

Human-PBL-SCID animals were created by intraperitoneal (i.p.) transfer of human peripheral blood lymphocytes (PBL) or PBL depleted of CD8-cxpressing lymphocytes (CD8dL). Analysis of human immunoglobulin levels in these animals revealed that severe combined immunodeficiency (SCID) mice receiving CD8dL produced significantly higher levels of serum human immunoglobulin than those receiving PBL. In an attempt to induce antigen-specific human antibodies these human-PBL-SCID animals were vaccinated with soluble protein antigen [ovalbumin (OVA)] entrapped within liposomes as an immunological adjuvant. Vaccination produced antigen-specific human IgM and IgG in human-PBL-SCID mouse serum. The use of liposomes as adjuvant and the reconstitution of animals with CD8dL together enhanced the OVA-specific immune response as evidenced by the detection of significantly increased serum antibody titres. In the CD8dL reconstituted group, solid tumours of human B-cell origin became detectable in the peritoneal cavity of animals at 8–10 weeks post-reconstitution. These turnouts were readily established in vitro and subsequent analysis of culture supernatants showed that these malignant cells continue to secrete human antibodies specific for the original immunizing antigen/n vitro, We believe this vaccination of the human-PBL-SCID mouse to produce antigen-specific human antibodies, may find use in the future production of human monoclonal antibodies and in the testing and development of novel vaccine/adjuvant systems. [ABSTRACT FROM AUTHOR]

Lymphokine-activated killer (LAK)-cell therapy has emerged as a new strategy in designing protocols for the treatment of cancer. However, in its present clinical form, it has not fulfilled the early promise shown in murine models of human metastatic disease. In an attempt to gain understanding as to why this might be the case, we measured the ability of human LAK cells, generated in vitro for 4 days, to kill LAK cells from the same donor that had been exposed to IL-2 in vitro for 8 days, and vice versa. In eight separate experiments using different donors, 4-day ('early') LAK cells were able to kill syngeneic 8-day ('late') LAK cells, while late LAK cells were also able to kilt early LAK cells. Strong killing was observed in both directions, which was almost total in one instance. In order to assess the development of this phenomenon, early LAK cells were tested for their ability to kill syngeneic LAK cells that were 1, 2, 3 or 4 days 'older' and the reciprocal experiment conducted using late LAK cells as effectors. The results illustrate a strong capacity for the development of syngeneic killing by human LAK cells. The possible implications of this phenomenon for the clinical administration of LAK cell/IL-2 therapy are discussed. [ABSTRACT FROM AUTHOR]

Stimulation of B lymphocytes from B-cell chronic lymphocytic leukaemia (B-CLL) with 12-0-tetradecanoylphorbol-13-acetate (TPA) has shown that these cells are capable of differentiation (Totterman, Nilsson & Sundstrom, 1980). Increases in the expression of different class II MHC antigens (Guy et al., 1983, 1986) and responsiveness to growth factors (Kabelitz et al., 1985; Suzuki, Butler & Cooper, 1985) have been studied. Supernatant from the human bladder carcinoma line T-24 contains a B-cell differentiation factor (BCDF) able to induce immunoglobulin secretion from CESS cells. We investigated the induction of proliferation and immunoglobulin secretion in human B cells by studying the effects of this factor on B-CLL cells, in both the presence and absence of TPA. We report here that this material (termed T-24.BCDF) causes immunoglobulin secretion to be initiated in these cells, and that this is not accompanied by detectable DNA synthesis. These observations were extended to normal human B cells and demonstrate that human B cells can secrete immunoglobulin in the absence of clonal expansion. [ABSTRACT FROM AUTHOR]

The immunopharmacological effects of interleukin-2 (IL-2) on the sensitization and effector phases of the delayed-type hypersensitivity (DTH) reaction were studied using contact sensitivity to the haptenizing agent dinitrochlorobenzene (DNCB), When administered at the time of priming to DNCB, IL-2 had no effect on the subsequent magnitude of the response. Interleukin-2 was, however, able to increase the magnitude of the response when given at the time of secondary challenge; the degree of change was directly related to the dose of IL-2. The proportions oft cells in the draining lymph node and spleen of IL-2-treated animals decreased by approximately one-third, but there was no alteration to the balance between CD4+ and CD8+ T cells. The results suggest that the increase in DTH observed was due to a pharmacological effect rather than to an increase in T-cell number. [ABSTRACT FROM AUTHOR]

Temporal arteritis (TA) is an acute vasculitis characterised by destruction of arterial architecture following infiltration of the arterial wall by macrophages, giant cells and lymphocytes. Using immunohistochemical techniques, tumour necrosis factor (TNF) was demonstrated in up to 60% of the cells in all areas of inflamed arteries. More cells staining for TNF were detected in the intima and media of inflamed vessels than control uninflamed arteries ( P<0.003 and P<0.001, respectively). In TA, TNF was localised to giant cells and macrophages, suggesting that its predominant source is from the monocyte lineage, but, occasionally, TNF staining was found in areas infiltrated by T cells. Many endothelial cells also contained TNF, but there were no differencs between the number of endothelial cells staining in inflamed and normal blood vessels. Of the two TNF receptors, the p75 receptor was sparsely represented in the inflamed vessels in TA. By comparison, the p55 receptor was widely detected on endothelial cells and infiltrating mononuclear cells close to the internal elastic lamina (IEL). Endothelial cells from normal vessels also stained for both TNF receptors, but normal smooth muscle cells in the vessel media expressed the p55 receptor, indicating that they are capable of responding to locally secreted TNF. Localisation of TNF receptors and TNF in close proximity to the IEL suggests that TNF could be involved in the leucocyte infiltration and arterial wall destruction characteristic of TA. [ABSTRACT FROM AUTHOR]

Aberrant expression of TGF-α is associated with human malignant oral epithelium. Experiments were initiated to determine the cellular sources of transforming growth factor-alpha (TGF-α) in human oral cancer. Ten freshly resected human oral cancers and four specimens of normal human oral epithelium were studied by in situ hybridization and immunohistochemistry. Tissues were probed with 35S-labeled sense and antisense riboprobes to (i) human TGF-α (hTGF-α), (ii) human epidermal growth factor receptor (EGFR) to determine the distribution of TGF-α responsive cells, and (iii) histone H3 to examine TGF-α and/or EGFR's possible contribution to altered proliferation in transformed epithelium. Results of our experiments showed that TGF-α mRNA could be detected in normal and transformed human oral epithelium. More surprising, we have identified the major source of TGF-α mRNA to be the infiltrating eosinophils. A monoclonal antibody to the mature human TGF-α peptide stained similar areas in normal and malignant specimens. Eosinophils associated with tumors exhibited positive cytoplasmic immunostaining for TGF-α protein. Labeling of EGFR mRNA in human oral epithelium demonstrated uniform labeling of basal layers in normal, hyperplastic, and mildly dysplastic epithelium. In severely dysplastic epithelium and carcinomas (particularly moderate to poorly differentiated types), cellular levels of EGFR mRNA were significantly higher. The profile of altered cellular levels of EGFR mRNA correlated well with the profile of altered proliferation as indicated by H3 mRNA labeling. We hypothesize that the overproduction of EGFR mRNA in tumor epithelium--together with the localized delivery of high amounts of TGF-α by eosinophils at tumor-developing sites-is responsible for the increased proliferation of the tumor epithelium. [ABSTRACT FROM AUTHOR]

The course of infection following s.c. inoculation of a wide dose range of L. mexicana stationary-phase promastigotes (SPP) was examined in sexually mature and immature NZB mice of both sexes. Infection with a high dose(> 107 SPP) was able to induce a protective in vivo response, which could be adoptively transferred with parasite-immune T cells, into naive, syngeneic recipients. In contrast. s.c. infection with a low close (<107SPP) induced non-healing lesions; disease susceptibility could also be transferred into naive animals with T cells From non-immune donors. When the ability to mount ai delayed-type hypersensitivity (DTH) reaction was tested in these two groups, the high-parasite dose group gave a significantly higher response. The in vivo protection and high DTH response were reflected in the ability of cells derived from the high-dose resistant (but not low-dose susceptible) mice to mount an antigen-specific T cell response in vitro. The possible immunological effector mechanisms underlying high-dose resistance and low-dose susceptibility are discussed. [ABSTRACT FROM AUTHOR]

Human peripheral blood mononuclear cells develop a powerful lytic capacity when cultured in vitro with interleukin-2 (IL-2), becoming lymphokine-activated killer cells (LAK cells). As part of an investigation into means of influencing this process, the effect of other cytokines has been examined. In this study we describe the ability of interleukin-6 (IL-6) to regulate the induction and function of human LAK cells. The results show that substitution of IL-6 for IL-2 did not lead to the development of functional LAK cells, nor was IL-6 able to alter the lytic capacity of established LAK cells. However, when IL-6 was included with IL-2 during the induction phase of the LAK cells, the resulting cells displayed considerably greater lytic activity than those prepared with IL-2 alone. This effect was IL-6 dose-related. These results indicate that LAK cell development may be positively regulated in vitro; the implications of this observation for the clinical usage of LAK cells are discussed. [ABSTRACT FROM AUTHOR]

Epstein-Barr virus (EBV)-transformed human B cells were seeded at densities below their capacity for autostimulatory growth and the effects of interleukin 1-alpha (IL-1-α), interleukin 1-beta(lL-l-β) and B-cell growth factor (BCGF) were studied. When added separately, IL-1-α was able to support the growth of EBV-transformed B cells, as was BCGF. In contrast, IL-1-β was unable to support the growth of these cells but was able to synergize with IL-1-α to promote cell growth. Further, the actions of BCGF and IL-1-α were seen to be synergistic, while those of BCGF and IL-1-β were not. The secretion of immunoglobulin was not affected by these reagents. These findings suggest separate, but complementary roles for the two forms of human IL-1 in B-cell growth. [ABSTRACT FROM AUTHOR]

We have cloned a number of cell lines from the human T-lymphocyte acute lymphoblastoid leukaemia (ALL) line CCFR-CEM, and attempted to construct functionally active human T-lymphocyte hybrids with them. Functional hybrids were generated using only one particular clone, 3H6. The activities found in the supernatants of two of these hybrids, D131G7 and DB2D10, are described. Supernatant from DB1G7 was found to suppress strongly the migration of normal human peripheral blood mononuclear cells, while that from DB2D10 was shown to inhibit the proliferative response of human T lymphocytes to both phytohaemagglutinin and concanavalin A. There was no cross-reactivity between the two supernatants, confirming the usefulness of the human T-lymphocyte hybrid technique in dissecting human T-lymphocyte function. The successful use of 3H6 is contrasted with the failure of another clone, 2H2, to permit the production of functional hybrids. Problems relating to the use of CCRF-CEM and its clones as parent cell lines in the production of human T-lymphocyte hybrids are discussed. [ABSTRACT FROM AUTHOR]

Genes and Immunity (2003) 4, 1–3. doi:10.1038/sj.gene.6363956 [ABSTRACT FROM AUTHOR]