Search

Graphical Abstract:

ABSTRACTAccurate prediction of the deviations/deformations is highly necessary for the new product development process. It is a tedious multi-tasking activity, in which various aspects need to be considered in the early phase of design. This paper proposes a new constitutive and collaborative framework to model the functional assembly geometry. For complex industrial applications in the multi-plant scenario, several departments work together for a common goal. Often the department’s goal is different and cannot achieve the feat of right for the first time. Hence this paper aimed to integrate the vital departments of the manufacturing industry. Initially, the functional assembly was predicted through Finite Element Analysis (FEA). A multi-layer perceptron type (MLP) artificial neural network was employed to learn the FEA behavior of the assembly. Further, the assembly prototype was practically tested to validate the FEA results, and the obtained data were used to verify the MLP network model. The best trained and tested network model was simulated to predict the near-net geometry considering the functional behavior of the assembly with external loads. The proposed method provides affirmative knowledge while integrating the finite element analysis, testing methods, and neural networks.

The cytochrome P45O activities of the naturally occurring Amaryllidaceae alkaloid narciclasine (3), isolated from Narcissus pseudonarcissus,and synthetic derivative trans-dihydronarciclasine (5) are reported. While narciclasine was found to possess potent inhibitory activity to human CYP3A4, its dihydro analogue was inactive. This study revealed that the C1−C10b double bond is required for inhibition of this crucial metabolizing enzyme. Compound 5also demonstrated no inhibition of the related human cytochromes CYP19 and CYP1A1. This study elevates the status of trans-dihydronarciclasine (5) as a highly privileged, readily available molecule, with potent and selective anticancer activity.

Scrap-battery collection, recovery and new-battery production activities in the battery industries have increased a large quantity of materials and products distribution between the facilities. This situation leads to the sustainability issue in terms of higher transportation cost, greenhouse gas (GHG) emission and drivers fatigue (long driving). In order to address the sustainable issues, the present closed loop supply chain network (CLSCN) is customised. The objective of this paper is to develop bi-objective multi product multi echelon multi period green CLSCN model with societal constraints (GCLSCN-SC) to minimise: 1) the sum of distribution centres' (DC) storage capacity expansion cost and transportation cost; 2) the GHG emission (CO2and NOx). The storage capacity expansion strategy and the transportation strategy are established in the proposed model to stimulate the bi-directional flow of the products and materials between facilities and the model is solved by using GAMS-23.5. The performance of proposed model has been compared with the present model and the evaluation demonstrates that the proposed model is efficient. The analysed results of the proposed model under different scenarios are presented in this paper.

Drilling is one of the material removal processes which are used in various manufacturing and assembly industries. The current growing and development technology in the drilling process is micro drilling. In this work, micro-holes are drilled on Inconel 718. The effects of various process parameters like feed, spindle speed and cutting tool diameter are used to study the response parameters like machining time, MRR, temperature and thrust force obtained during micro drilling. Experiments are carried out based on Taguchi L27 orthogonal array design using Tungsten carbide drill bit and Inconel 718 as work material. Feed rate is varied from 1 to 3 mm/min, Spindle speed ranges from 16,000 to 26,000 rpm and diameter of the tool also varied from 0.4 mm to 0.8 mm. It is observed that temperature is increasing with increase in speed and feed. When the tool diameter, feed rate and spindle speed increases material removal rate (MRR) also increases. The machining time decreases with increase in feed rate, also the cutting force increase with the increase in tool diameter, feed rate and spindle speed. The optimal combination of the process parameter is found out using grey relational analysis (GRA).

Background In spite of the significant progress in modern medicine, viruses continue to be a formidable challenge to human health. The use of plants for the remediation of viral-borne diseases stretches back to the very dawn of mankind. Among bulbous plants, the Amaryllidaceae is one of the most popular families exploited in the traditional remediation of infectious diseases.Methods This account details the findings from a literature search carried out on the antiviral properties of the Amaryllidaceae. The keyword engaged in the search was “antiviral” in combination with the words “Amaryllidaceae,” “Amaryllidaceae specie,” and “Amaryllidaceae alkaloid.”Results Thirty-six taxa from 13 countries, notably in Africa and parts of Asia, have been cited as traditional remedies for viral diseases. Alcoholic bulb extracts of 18 species were evaluated against 23 different pathogens from 13 viral families. A wide range of activities was observed, with the whole-plant methanol extract of Zephyranthes candidaseen to be the most striking (IC500.0019 µg/mL against poliovirus). The active principles in the main were isoquinoline alkaloids, of which lycorine impressed against the Avian influenza virus (strain H5N1). The mechanisms underlying the antiviral effects were seen to be related to the inhibition of DNA, RNA, and protein synthesis as well as inhibitory effects toward reverse transcriptase and protease enzymes.Conclusion Amaryllidaceae provides a richly diverse platform for antiviral drug research. Such endeavors have been fortified by the significant amounts of information emerging from indigenous knowledge systems. Ongoing studies will continue to target the active entities, particularly from taxa with verifiable ethnomedicinal backgrounds.

The present work deals with feature-based modelling (FBM) and process parameters selection in a computer-aided process planning (CAPP) system for prismatic micro parts. The proposed system maps the Extensible Markup Language (XML) data from the feature-based model and produces the corresponding process parameters required for micro part manufacturing. It has two components: (1) invention of FBM and automatic extraction of manufacturing feature information and (2) selection of process parameters for the given micro features using knowledge-based system (KBS) approach. An attempt has been made to develop process parameters based on experimental investigation and optimisation using genetic algorithm (GA) apart from the information from literatures and user manuals used for database development. FBM and data extraction through XML files avoid complex feature extraction and recognition processes. The application of the proposed system was verified with the case study. The present system is intended for miniature part with micro drill and mill features. Incorporation of more micro features and consideration of various other process planning activities ensures a complete CAPP system for prismatic micro parts.

Composite materials are increasingly used in aerospace, naval and automotive vehicles due to their high specific strength and stiffness. In the area of Non destructive testing, ultrasonic C-scans are used frequently to detect defects in composite components caused during fabrication and damage resulting from service conditions. Ultrasonic testing uses transmission of high frequency sound waves into a material to detect imperfections or to locate changes in material properties. The most commonly used ultrasonic testing technique is pulse echo and through transmission wherein sound is introduced into a test object and reflections (echoes) are returned to a receiver from internal imperfections. Under low-velocity impact loading delaminating is observed to be a major failure mode. This report presents the use of above two techniques to detect the damage in glass fiber reinforced plastic (GFRP) laminates. Pulse echo is used to locate the exact position of damage and through transmission is used to know the magnitude of damage in composite. This paper work will be carried out on two different thicknesses and at impact energy levels varying from 7 to 53J. The ensuring delamination damage will be determined by ultrasonic C-scans using the pulse-echo immersion method for through transmission. Delamination areas were quantified accurately by processing the raw image data using a digital image processing technique. Based on the data obtained, correlation will be established between the delamination area and the impact energy.

Narcissus serotinusbelongs to the Amaryllidaceae family, a group well known for an exclusive variety of alkaloids with interesting biological activities. This study was aimed at identifying the alkaloid constituents of N. serotinuscollected in the Spanish region of Valencia, using a combination of chromatographic, spectroscopic, and spectrometric methods, including GC-MS and 2D NMR techniques. GC-MS analysis allowed for the direct identification of five known compounds. In addition, the isolation and structure elucidation of six new Amaryllidaceae alkaloids are described.

This paper deals with the use of Taguchi technique with fuzzy logic to optimise electrochemical micromachining (EMM) process with multiple quality characteristics. The truncated cone tip electrode produced the highest machining rate and the conical with rounded tip electrode produced holes with lesser overcut. Hence, achieving higher machining rate with lesser overcut can be considered as a multi-objective optimisation problem. The machining parameters (the tool electrode tip shape, machining voltage, pulse on-time, electrolyte concentration) are optimised with considerations of the multiple performance characteristics (machining rate and overcut). The experiments were conducted in the developed EMM set-up. The experimental results reveal that the conical with rounded electrode, machining voltage of 9 V, pulse on-time of 10 ms and electrolyte concentration of 0.35 mole/l is the optimum combination for higher machining rate and lesser overcut. In addition in-depth studies have also been made to examine the influence of tool electrode tip on the overcut through SEM micrographs of machined micro-hole.

The allocation of tolerances for the components of a mechanical assembly strongly influences manufacturing cost and functional performance. In order to get a reliable tolerances and costs, it is necessary to obtain manufacturing cost-tolerance models. Traditionally, these models are established by various curve-fitting techniques using empirical experimental data. Existing empirical models, however, have considerably large model fitting error, inconsistent modelling accuracy over the tolerance range of typical manufacturing processes. Using these mathematical models will introduce a considerably large error in optimal design of component tolerances. This work presented in this paper uses an artificial neural network (ANN), to overcome above limitations, for establishing manufacturing cost-tolerance models for various manufacturing processes. Having built the ANN cost-tolerance models, continuous ant colony optimisation (CACO) algorithm is used to obtain optimum combination of tolerances for minimum manufacturing cost. A typical tolerance design example is used to illustrate the effectiveness and reliability of the proposed approach.

A survey of substitution reactions conducted in a phosphonium bistriflimide ionic liquid is presented. The results demonstrate high selectivity favoring substitution over typically competitive elimination and solvolytic processes even when challenging secondary and tertiary electrophiles are employed. The first reports of Kornblum substitution reactions in an ionic liquid are described that proceed with very high chemoselectivity in favor of nitro over nitroso products and elimination side products. The structure–reactivity study indicates that these reactions proceed through a narrow spectrum of pathways ranging from straight SN2 to a preassociation pathway along a saddle point that approaches the SN1 limit. The barrier to the formation of dissociated carbocations is attributed to the structural features of this ionic liquid that favor intervention of the associated nucleophile over dissociation, also preventing cross over to E1 processes. The lack of any basic entity in the phosphonium bistriflimide ionic liquid appears to prevent any potential base‐mediated elimination reactions, which makes this a highly selective medium for use in general substitution reactions.

A previous investigation in our laboratory showed that virtual environment users rely on image velocity errors rather than image displacement errors to sense head-tracking latency. In that study, the effect of image displacement error may have been suppressed because its peak amplitudes were associated with higher head velocity, which is thought to suppress visual motion sensitivity. To determine whether diminished motion sensitivity could play a role in user discrimination of latency, we investigated whether subjective perception of image motion comparable to that caused by latency is impaired by concurrent horizontal or vertical head movement. Eight participants monocularly viewed a checkerboard pattern in a head-mounted display that was oscillated from side-to-side with half peak-to-peak amplitudes from 0° to 5.64°. Perceptual sensitivity to image motion amplitude was reduced by almost half, during 30° repetitive horizontal head movements at 0.4 Hz. Accordingly, the reduced sensitivity to motion during head movement appears to be a phenomenon that modulates users' tolerance of erroneous image motion caused by virtual environment latency.

A catalyst system consisting of a chromium source, a 2,6-disubstituted phenol and an aromatic ether solvent, on activation with triethylaluminium, is active and selective for the trimerisation of ethylene to form 1-hexene. The aromatic ether appears to play a role as both solvent and reagent and is pivotal in ensuring both the good activity of the system as well as selectivity to the desired product, 1-hexene.

Since vascular endothelial growth factor (VEGF) plays a major role in tumor angiogenesis, we determined whether blockage of VEGF receptor signaling using a novel tyrosine kinase inhibitor (PTK 787) decreases the growth and metastasis of human pancreatic carcinoma growing orthotopically in nude mice. Human pancreatic L3.6pl cells were injected into the pancreas of nude mice. Seven days later, groups of mice were given daily oral administrations of PTK 787 alone, twice weekly i.p. injections of gemcitabine, or combination therapy. The mice were necropsied when control mice became moribund (day 35). Therapy with PTK 787 alone, gemcitabine alone, or the combination of both agents produced respectively 60%, 70%, and 81% inhibition in the volume of pancreatic cancers. The combination therapy significantly decreased the incidence of lymph node and liver metastasis, leading to a significant increase in survival. Microvessel density (MVD) was significantly decreased in tumors treated with either PTK 787 alone or PTK 787 plus gemcitabine. MVD directly correlated with tumor cell proliferation and inversely correlated with apoptosis of tumor cells and associated endothelial cells. Collectively, our results demonstrate that blockade of VEGF-R signaling may provide an additional approach to the therapy of pancreatic cancer.

Astrocytoma vasculature patterns differ according to histological grade of malignancy with glioblastoma multiforme (WHO grade IV) showing most extensive endothelial proliferation. Here, we determined whether the vascular patterns of medulloblastoma and supratentorial primitive neuroectodermal tumors (PNETs), which can be hardly distinguished histopathologically, differ. We evaluated the spatial organization of vessels in medulloblastomas and PNETs using antibodies to von Willebrand factor (vWF) and CD34. Medulloblastoma capillaries showed slight endothelial cell hyperplasia. Microvessels sprouted from the capillaries and formed glomeruloid clusters. There were areas with chains of unopposed endothelial cells (3–10 cells). Supratentorial PNETs had highly branched capillaries with extensive endothelial cell hyperplasia. Glomeruloid arrays of microvessels extended from the capillaries. Small fragments of endothelial tubes were scattered throughout the tumor. Therefore, medulloblastomas and supratentorial PNETs showed different spatial organization of tumor vessels which can be used for differentiation of each tumor entity. These vascular patterns may reflect different tumor derived angiogenic stimuli.

Cell adhesion receptors of the integrin superfamily, CD44, and adhesion receptors of the immunoglobulin superfamily are expressed by high‐grade astrocytic tumors of the central nervous system. These receptors are critical for the invasion of these tumors in the nervous system. Glioma cells utilize these receptors to adhere to and migrate along the components of the extracellular matrix, which is uniquely distributed and regulated within the brain and the spinal cord. For this reason, glioma cell invasion into the adjacent brain tissue is dependent on the interaction of glioma cells with the extracellular matrix. The receptor‐ECM component interaction is discussed, focusing on the role of cell adhesion molecules of the integrin family and CD44 in glioma cell adhesion and invasion. Microsc. Res. Tech. 43:250–257, 1998. © 1998 Wiley‐Liss, Inc.

Cell adhesion receptors of the integrin superfamily, CD44, and adhesion receptors of the immunoglobulin superfamily are expressed by high-grade astrocytic tumors of the central nervous system. These receptors are critical for the invasion of these tumors in the nervous system. Glioma cells utilize these receptors to adhere to and migrate along the components of the extracellular matrix, which is uniquely distributed and regulated within the brain and the spinal cord. For this reason, glioma cell invasion into the adjacent brain tissue is dependent on the interaction of glioma cells with the extracellular matrix. The receptor-ECM component interaction is discussed, focusing on the role of cell adhesion molecules of the integrin family and CD44 in glioma cell adhesion and invasion. Microsc. Res. Tech. 43:250–257, 1998. © 1998 Wiley-Liss, Inc.

Cell membranes contain numerous species of glycosphingolipids (GSL) and glycerophospholipids. Changes in the surface expression of these moieties that accompany malignant transformation are potential targets for immune therapies. There is increasing evidence that tumour specificity resides in the carbohydrate composition and topography of gangliosides and in the asymmetric distribution of phospholipids in the bilayer membrane. However, since these epitopes are not antigenic, circumvention of immunological tolerance to these ‘self antigens’ is required to generate an effective immune response. New methodologies accomplish this by coupling these hapten-like lipid epitopes to immunogenic protein carriers. Indeed, the generation of immune responses to endogenous lipid antigens occurs in several autoimmune syndromes and may serve as natural models for therapeutic immune intervention that influence pathways critical to tumour angiogenesis, proliferation and apoptosis.

Summary The effect of puromycin on spinal cord regeneration was studied following implantation into the site of spinal cord hemi- or transection of Gel-foam saturated with puromycin (1mM) in a saline carrier, implantation of Gel-foam sponge saturated with saline (carrier control), or lesion alone (lesion control). The spinal cords of 107 rats were studied with light and electron microscopy 7, 14, 30, 60 and 90 days postoperative (DPO). Spinal cord hemisected animals developed a dense cicatrix at the site of lesion replete with connective tissue, blood vessels, and myelinated and unmyelinated nerve fibres which could be traced to peripheral sources. Rostrally at the C.N.S.-cicatrix interface, there were reactive neuroglial cells, occasional nerve fibres and finger-like projections of spinal cord (due to cavitation lesions) which contained neuroglia, axons and dendrites. Implantation of saline in Gel-foam resulted in the same morphology as in hemisected animals except for increased lesion size due to mechanical factors and decreased cicatrix density during the first 30 DPO. Puromycin treatment resulted in a cicatrix with initial decreased cell density but which contained a new class of nerve fibres at 30 DPO. These nerve fibres were oriented in a rostro—caudal direction, were unmyelinated, 0.1–0.2 µm in diameter and had expanded smooth endoplasmic reticulum. Some of these nerve fibres were degenerating at 30 DPO and all were absent by 60 DPO. The puromycin-treated spinal cord within 200 µm rostral to the basal lamina contained nerve terminal conglomerates, which resembled boutons, in fascicles from 30–90 DPO (duration of experiment). Hemisection of the spinal cord by crushing 1-11/2 segments rostral to the site of puromycin implantation at 30 DPO resulted in degeneration of these nerve fibres in the cicatrix as well as the degeneration of nerve terminal conglomerates just rostral to the basal lamina. The regenerative capacity of the spinal cord is discussed in relationship to these findings.

Alterations in the immunogenic properties of tumor cells frequently accompany selection for multipledrug-resistant (MDR) variants. Therefore, studies were performed to examine the hypothesis that overexpression of membrane P-glycoprotein, commonly observed in MDR tumor cells, is associated with enhanced immunogenic properties. Immunogenicity was determined by (a) the ability of drug-sensitive parental UV2237M fibrosarcoma cells and drug-resistant UV2237M variant cells to immunize normal mice against rechallenge with parental tumor cells and (b) the ability of normal syngeneic mice to reject cell inocula that caused progressive tumor growth in immunocompromised mice. Variant UV2237M cell lines included subpopulations selected for a six- to ten-fold increase in mRNA for P-glycoprotein and expression of the MDR phenotype (resistance to doxorubicin) and cells sensitive to doxorubicin (and no expression of MDR properties) but resistant to ouabain. All UV2237M drug-resistant cells were highly immunogenic in immunocompetent mice, regardless of their MDR phenotype. Additional studies showed that CT-26 murine adenocarcinoma cells, sensitive or resistant to doxorubicin (expressing high levels of P-glycoprotein), injected into normal syngeneic Balb/c mice produced rapidly growing tumors. The data do not demonstrate a correlation between the immunogenic properties of drug-resistant tumor cells and the expression of P-glycoprotein.

Summary We determined whether the intravenous administration of multilamellar vesicle liposomes (MLV) containing a lipopeptide analogue of a fragment from the cell wall of gram-negative bacteria (CGP 31 362) can render BALB/c mouse alveolar macrophages tumoricidal in situ and reduce the incidence of spontaneous lung metastasis of syngeneic renal carcinoma (RENCA) cells. Alveolar macrophages (a) incubated in vitro with MLV containing CGP 31 362 (MLV-31 362) and (b) harvested from mice injected i.v. with MLV-31 362 were rendered cytotoxic against the RENCA cells. Maximum cytotoxic activity of the macrophages was induced by injecting 5 µmol MLV consisting of 250 mg phospholipids and 0.5 mg CGP 31 362. The single i.v. injection of 5 µmol MLV-31 362 produced activation of macrophages that lasted for up to 4 days. Repeated i. v. injections of MLV-31 362 produced a continuous antitumor activity in alveolar macrophages. To study the lipopeptide's effects on metastasis, we injected the left kidneys of BALB/c mice with RENCA cells. The kidney with growing tumor was resected 10 days later and, after a further 2 days, groups of mice were injected i.v. with MLV-31 362 or with MLV-HBSS (twice weekly for 3 weeks). Treatment with MLV-31 362 significantly decreased the median number of spontaneous lung metastases. These data demonstrate that the systemic administration of MLV-31 362 can activate murine lung macrophages in situ and reduce the incidence of spontaneous RENCA lung metastases.

Tumor cell subpopulations were isolated from parental (drug-sensitive) L1210 tumor by lectinnylon chromatography and evaluated in active, specific immunotherapy of a thioguanine-resistant L1210 subline. Cells released by mannoside were effective in causing regression of the variant subline. This effectiveness was not altered by treatment of the subpopulation with neuraminidase. Subpopulations either not binding fucose-specific columns or released from glucose-specific columns were also effective immunogens. Studies using the syngeneic EL4 lymphoma model indicated that mannoside-released cells were effective in combination chemotherapy-immunotherapy. The results further demonstrate the feasibility of this approach to active, specific immunotherapy.

L1210 tumor subpopulations were isolated by lectin-nylon chromatography and evaluated in active, specific immunotherapy of residual L1210 leukemia (following reduction in tumor burden by chemotherapy). Immunotherapy with cells either not binding mannosylspecific columns or eluted from fucose-specific columns resulted in a higher percent of long-term survivors compared to mice treated with chemotherapy only. In contrast, immunotherapy with cells eluted from galactose-specific columns was deleterious, and abrogated the beneficial effects of chemotherapy. The results emphasize that (a) clinical immunotherapy may be either beneficial or deleterious, depending upon the properties of the tumor cell vaccine, and (b) the therapeutic value of L1210 subpopulations is related to the expression of cell-surface carbohydrates.

Active, specific immunotherapy of L1210 leukemia (following reduction in tumor burden by chemotherapy) with an L1210 tumor cell subpopulation (con A-Fraction A) depended upon the integrity of cell-surface constituents. The immunotherapeutic value of con A-Fraction A cells was abrogated by treatment of the cells with either neuraminidase or galactosidase, and mice treated with these cells died faster than mice treated with chemotherapy alone. Glucosidase and protease treatment totally destroyed the immunogenicity of the tumor cell vaccine. The results suggest that the immunogenic properties of this vaccine may reside in the cell-surface expression of glycoprotein.

BDF1 mice bearing L1210 leukemia were treated with chemotherapy or in combination with neuraminidase-treated cells and BCG. Histological evaluation was done on these mice at various intervals after therapy in order to determine the rate and extent of metastatic involvement in various tissues and organs. Results were compared to tumor-bearing mice which were not treated. In all animals, tissues were classed as having minimal involvement, moderate involvement or maximal involvement based on a scale of 0 through 4. Results indicated that: (a) mice which were long term survivors did not completely reject their tumor for weeks after treatment with chemotherapy and immunotherapy; (b) complete tumor rejection did not indicate a restoration of normal tissue integrity; and (c) failure of chemotherapy-immunotherapy had no consistent pathology, but was probably due to tumor distribution rather then tumor burden per se.

BCG, C. parvum, and reovirus were used as immunostimulants in treating murine mammary adenocarcinoma (A-10) after tumor burden had been minimized with BCNU. Immunostimulants were administered at different times with respect to chemotherapy. Different doses were used to determine the optimal response as measured by survival. BCG induced the best response when 6.67×105 organisms were given 2 days after chemotherapy. The optimal response with C. parvum was observed after a dose of 0.35 mg was given 1 or 2 days after chemotherapy. Similarly, reovirus produced the best response when 1010 plaque-forming units were given 2 days after chemotherapy. These data are consistent with previous findings and support the notion that immunostimulants require an appropriate lymphoid substrate in order to induce an adequate anti-tumor response.

EL4 lymphoma was grown as an ascitic tumor in the peritoneal cavity of C57Bl/6 mice. Animals with different tumor burdens (either 107or 109cells) were treated with a single intraperitoneal injection of BCNU using doses from 20–40 mg/kg. Response as measured by mean survival time and percent survival was dependent on tumor burden and dose of drug. The objective of chemotherapy was to increase the mean survival time, but not the percent survival, in order to evaluate the therapeutic effect of reovirus. Mice were given 108, 109, or 1010Pfu of reovirus at various times with respect to chemotherapy. The number of mice cured after treatment with both BCNU and reovirus was significantly greater compared to mice treated with BCNU only. Mice cured with combination therapy developed tumor-specific immunity as measured by cytotoxic lymphocytes and serum, and resistance to a lethal tumor challenge.

The use of isolated tumor cell subpopulations combined with nonspecific immunostimulation (BCG and C parvum) was studied in the L1210-B6D2F1 tumor-host model. Some tumor cell vaccines abrogated the immunotherapeutic value of nonspecific immunostimulants. A tumor cell vaccine prepared from a subpopulation with no apparent immunotherapeutic value completely neutralized the excellent therapeutic value of C parvum in this tumor-host model. The results emphasize the limitations of immunotherapy, and also the need to understand fundamental relationships between the immunological status of the host and subsequent immune stimulation.

and The therapy of cancer is, in reality, the design of therapeutic strategies for therapy of metastatic disease. Metastases consist of unique subpopulations of tumor cells that are derived from the primary tumor, colonize distant target organs, and are able to subvert host immune responses, establish necessary angiogenesis, and obtain a sufficient nutrient supply while evolving to become autonomous from homeostatic mechanisms that function within normal, differentiated tissues. Attempts at eradication of metastases by conventional therapies have generally been unsuccessful due to genetic instability and heterogeneity of metastatic tumors; these properties lead to the emergence of tumor cells that are resistant to most conventional treatments. It may be possible to circumvent this heterogeneity by the activation of tissue macrophages to the tumoricidal state. Activated macrophages are able to kill tumor normals while sparing normal tissues, and efficient activation can be achieved by encapsulation of synthetic muramyl tripeptide analogues into multilamellar vesicles composed of phospholipids. Systemic administration of these liposome-encapsulated compounds leads to tumoricidal activation of alveolar and peritoneal macrophages and eradication of established tumor metastasis in numerous animal tumor models, and this form of therapy is enhanced by combination with parenteral administration of cytokines. Phase III clinical trials of recurrent osteosarcoma are currently in progress. Modulation of the tumor microenvironment by activated macrophages may prove to be an additional modality in treatment strategies that combine the use of biological response modifiers with conventional therapies.

Abstract. We previously have shown that melittin evokes a sustained increase in plasma corticosterone levels of the female rat. Significant increases occurred only during the morning and the duration of the response was increased from 48 h to 8 days by a second milittin injection 3 days after initial exposure to melittin. To further evaluate the effect of melittin on adrenocortical function, rats were given melittin at 09.00 h on days 1 and 4 and on day 8 rats were subjected to a variety of different stresses. Saline-injected rats served as controls. Blood for determining non-stress and stress levels of corticosterone concentration (RIA) was collected by decapitation. In all cases morning but not afternoon non-stress plasma corticosterone levels of melittin-injected rats were higher than those of saline-injected controls; afternoon non-stress corticosterone levels did not differ between groups. Melittin- and saline-treated rats showed comparable corticosterone responses to a morning 2-min restraint stress. In contrast, melittin treatment facilitated the pituitary-adrenal response to rotational and surgical stress as well as the stress of removing one rat from a cage of two. Fifteen min after removal of the first rat of a cage of two, plasma corticosterone levels of the melittin-injected rat were significantly higher than those of saline-injected rats. Likewise, plasma corticosterone levels of melittin-treated rats were higher (P< 0.05) than those of saline-injected rats 15 min after rotational (10 rpm) and surgical (jugular cutdown and blood withdrawal) stress. Collectively these data indicate that exposure to melittin (and/or the resulting increase in morning corticosterone levels) may have a significant influence on the pituitary-adrenal responsiveness to stress.

We investigated the expression of cytokine genes and tumoricidal properties in human blood monocytes in response to a new synthetic immunomodulating lipopeptide, JBT3002. Incubation of peripheral blood monocytes with free‐form JBT3002 or JBT3002 encapsulated in multilamellar phospholipid vesicles (liposomes, MLV‐JBT3002) induced tumoricidal properties in a dose‐dependent manner. Both MLV‐JBT3002 and free‐form JBT3002 induced production of tumor necrosis factor α, interleukin‐1β, and interleukin‐6 in a dose‐dependent manner with similar kinetics. Treatment of monocytes with interferon‐γ did not significantly alter the expression of cytokine genes but increased the expression of cytokines induced by MLV‐JBT3002 and free‐form JBT3002. In contrast to monocyte activation by lipopolysaccharide (LPS), activation by JBT3002 was independent of serum and was not inhibited by CD14‐neutralizing antibody. Incubation of monocytes with JBT3002 induced a rapid increase in tyrosine phosphorylation of proteins with apparent molecular masses of 42 and 38 kDa, a migration band shift of c‐Jun NH2‐terminal kinase 1 (JNK1), and activation of extracellular signaling regulated kinases. Consistent with its effect on cytokine expression, stimulation of these intracellular signaling pathways by JBT3002 was not inhibited in serum‐free conditions. Collectively, the data indicate that the synthetic lipopeptide JBT3002 is a potent monocyte activator that modulates monocyte function by mechanisms similar to LPS but by a distinct receptor. J. Leukoc. Biol. 63: 766–774; 1998.

Although humoral responses to Borrelia burgdorferi(Bb) have been shown to be protective in some animal models of Lyme disease, the role of T cells in this disease is less well understood. This work describes three Bb‐specific T cell lines that prevent disease progression in syngeneic mice. The T cell lines were generated in C3H mice immunized with Bb in complete Freund's adjuvant. All lines were Bb‐specific, CD4+, TCRαβ+, and they proliferated and produced interferon‐γ and interleukin‐2 on stimulation with Bb. Injection of the cell lines into naive C3H recipients significantly reduced the number of organisms recoverable from the blood and tissues of infected mice and protected them from developing Bb‐induced periarthritis. These studies demonstrated that Th1 cells can confer resistance to Bb infection in susceptible mice and suggested that the timing of this T cell response may be critical for determining disease outcome. J. Leukoc. Biol. 63: 542–549; 1998.

These studies were designed to develop an orthotopic model for human bladder cancer and to isolate variant metastatic cell lines.

Individual astrocytoma cells expressing a cytoplasmic form of p185c-neu migrated along basement membrane lined surfaces after xenografing fresh low or high grade human malignant astrocytomas into host rat brain. We now study the migratory capacity of fresh human malignant astrocytoma cells seeded on hydrated gel wafers composed of artificial basement membrane or collagen I, a normal and lesion-related CNS extracellular matrix component. Approximately 107 mechanically disrupted cells (with small clumps) of 3 fresh low grade and 6 fresh high grade astrocytomas were seeded on the surface of artificial basement membrane and collagen I wafers (11 × 16 mm). The wafers were then prepared for scanning electron microscopy and immunohistochemstry at 1, 3, 5, and 7 days after seeding. Regardless of tumor grade, a morphologically similar class of cells was observed to migrate through collagen I gels in 24 hours and 0.5–1.5 mm into artificial basement membrane gels in 7 days. Immunohistochemistry revealed that the migrated cells from low and high grade astrocytomas were positive for glial fibrillary acidic protein (GFAP)) and expressed cytoplasmic human-specific p185c-neu. These data indicate that fresh human malignant astrocytoma cells that contain GFAP and express cytoplasmic p185c-neu have a high degree of migratory capacity and could be the cell in the tumor involved in intraparenchymal metastasis and poor patient survival in high grade astrocytomas of the human brain.

Current therapy of human superficial bladder cancer includes the intravesical administration of antitumor drugs and immunomodulators. The purpose of these studies was to determine whether phospholipid liposomes that bind to human bladder cancer cells can improve the delivery of interferon alpha (IFN-α) to neoplastic urothelium. The antiproliferative activity of free IFN-α and IFN-α encapsulated in liposomes was assessed in vitro against the human transitional cell carcinoma line 253J. The cells were exposed to free and liposome-encapsulated IFN-α for short periods ranging from 30minutes to four hours, and inhibition of cell growth was determined three days later. The production of >25 percent cytostasis of 253J cells by free IFN-α required four hours of continuous exposure. In contrast, IFN-α encapsulated in liposomes produced 35 percent and 60 percent cytostasis after a 30-minute and four-hour exposure, respectively. Liposome-encapsulated IFN-α was also effective (50 percent cytostasis) against a subline of 253J cells selected for resistance against free IFN-α. Liposomes containing IFN-α were stable in the presence of human urine. In vivo studies in mice showed that intravesical administration of radiolabeled IFN-α or radiolabeled liposomes did not yield significant systemic absorption and deposition in distant organs. Collectively, these results suggest that the encapsulation of IFN-α within multilamellar liposomes may augment its antiproliferative activity, overcome some forms of tumor cell resistance to IFN-α, and prove useful for intravesical therapy of superficial bladder cancer. (J. Urol, 143:1252-1260, 1990)

Summary To study the regenerative capacity of the spinal cord in adult rat, presynaptic boutons were classified as S (spherical vesicles), F (flattened vesicles) and C complexes, and analysed statistically on a-motoneuron somata and lamina VII interneurons on the operated side in the first segment rostral to a spinal cord hemisection. Following chloral hydrate anaesthesia left spinal cord hemisections were made on twenty adult rats (225 gms) at vertebral level T-2. Animals were prepared for electron microscopy at 7, 14, 30, 45, 60 and 90 DPO and compared with normals. All counts were made on coded material and subjected to statistical analysis. The normal frequency of presynaptic bouton types on a-motoneuron somata and primary dendrites was altered over the entire postoperative period. S presynaptic boutons were increased on a-motoneuron somata at 30 DPO. At 45 DPO, massive degeneration with concomitant synaptic remodeling resulted in a return to near normal frequencies of S and F presynaptic boutons. At 60 and 90 DPO a gain in S presynaptic boutons and a concomitant loss in F presynaptic boutons resulted in frequencies different from normal and decreased absolute numbers of presynaptic boutons. The interneuron somata also exhibited alterations over the postoperative period. There was a reversal of frequency of presynaptic boutons at 45 DPO. However unlike on a-motoneuron somata the frequency of S and F presynaptic boutons returned to normal at 60 and 90 DPO. The a-motoneuron somata appeared to be cyclically and nonselectively reinnervated by ventral horn interneurons over 90 DPO.

C57BL/6 mice (haplotype H-2b) were alloimmunized by a classical protocol using repeated injections of DBA/2 spleen and liver cells (H-2d). The resulting polyclonal, hyperimmune antisera were highly cytotoxic to untreated and neuraminidase- (VCN)-treated DBA/2 spleen cells. An unexpected result was that the anti-H-2dsera were also cytotoxic to VCN-treated C57BL/6 spleen cells. The cytotoxicity was limited to an IgM antibody and could be evoked by a single alloimmunization. The results demonstrate a new feature of the classical immune response, autoantibodies against a common, though cryptic murine antigen, designated Mol.